U.S. patent number 11,097,520 [Application Number 16/564,569] was granted by the patent office on 2021-08-24 for laminate, method of manufacturing laminate, and method of manufacturing antireflection film.
This patent grant is currently assigned to FUJIFILM Corporation. The grantee listed for this patent is FUJIFILM Corporation. Invention is credited to Yuta Fukushima, Shuntaro Ibuki.
United States Patent |
11,097,520 |
Fukushima , et al. |
August 24, 2021 |
Laminate, method of manufacturing laminate, and method of
manufacturing antireflection film
Abstract
A laminate includes a support, a layer (b) including a pressure
sensitive adhesive, particles (a2) having an average primary
particle diameter of 100 nm to 380 nm, and a layer (ca) including a
resin, in which the layer (b) is provided closer to the support
than the layer (ca), the particles (a2) are buried in a layer
obtained by combining the layer (b) and the layer (ca) and
protrudes from an interface of the layer (ca) on the support side,
and a portion including the particles (a2) and the layer (ca) is
peelable from the layer (b).
Inventors: |
Fukushima; Yuta (Kanagawa,
JP), Ibuki; Shuntaro (Kanagawa, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
FUJIFILM Corporation |
Tokyo |
N/A |
JP |
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Assignee: |
FUJIFILM Corporation (Tokyo,
JP)
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Family
ID: |
1000005760974 |
Appl.
No.: |
16/564,569 |
Filed: |
September 9, 2019 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20190391296 A1 |
Dec 26, 2019 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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PCT/JP2018/005874 |
Feb 20, 2018 |
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Foreign Application Priority Data
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Mar 31, 2017 [JP] |
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JP2017-072558 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B32B
7/12 (20130101); B29C 65/48 (20130101); B32B
27/20 (20130101); B29C 65/4825 (20130101); B29C
66/73366 (20130101); B29C 65/76 (20130101); B29C
66/45 (20130101); B32B 2264/301 (20200801); Y10T
428/25 (20150115); B32B 7/06 (20130101); B29C
66/73343 (20130101) |
Current International
Class: |
B32B
27/20 (20060101); B29C 65/48 (20060101); B29C
65/00 (20060101); B29C 65/76 (20060101); B32B
7/06 (20190101); B32B 7/12 (20060101) |
Field of
Search: |
;156/60,230,235,247,272.2,273.3,273.5,275.5,275.7,289,297,298,307.1,307.7
;359/601,614,586 ;428/221,323,331,332,333,338,339 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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07-104103 |
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Apr 1995 |
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JP |
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11-271506 |
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Oct 1999 |
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JP |
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2012-086475 |
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May 2012 |
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JP |
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2016-095498 |
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May 2016 |
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JP |
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2017/006936 |
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Jan 2017 |
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WO |
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Other References
Office Action, issued by the Japanese Patent Office dated Apr. 21,
2020, in connection with Japanese Patent Application No.
2019-508760. cited by applicant .
International Search Report Issued in PCT/JP2018/005874 dated May
1, 2018. cited by applicant .
Written Opinion Issued in PCT/JP2018/005874 dated May 1, 2018.
cited by applicant .
International Preliminary Report on Patentability issued in
PCT/JP2018/005874 dated Oct. 1, 2019. cited by applicant.
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Primary Examiner: Tolin; Michael A
Assistant Examiner: Slawski; Brian R
Attorney, Agent or Firm: Edwards Neils LLC Edwards, Esq.;
Jean C.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a Continuation of PCT International Application
No. PCT/JP2018/005874 filed on Feb. 20, 2018, which was published
under PCT Article 21(2) in Japanese, and which claims priority
under 35 U.S.C .sctn. 119(a) to Japanese Patent Application No.
2017-072558 filed on Mar. 31, 2017. The above applications are
hereby expressly incorporated by reference, in their entirety, into
the present application.
Claims
What is claimed is:
1. A method of manufacturing a laminate, comprising, in this order:
a step (1) of providing particles (a2) having an average primary
particle diameter of 100 nm to 380 nm and a curable compound (a1)
on a temporary support in a thickness in which the particles (a2)
are buried in a layer (a) including the curable compound (a1); a
step (2) of curing a portion of the layer (a) to obtain a layer
(ca); a step (3) of bonding a layer (b) of a pressure sensitive
film having a support and the layer (b) including a pressure
sensitive adhesive on the support, to the layer (ca); a step (4) of
causing a position of an interface of the layer (ca) on a side of
the support to come close to a side of the temporary support such
that the particles (a2) are buried in a layer obtained by combining
the layer (ca) and the layer (b) and protrude from the interface of
the layer (ca) on the side of the support; and a step (5) of
peeling the temporary support.
2. The method of manufacturing a laminate according to claim 1,
further comprising: a step (4-2) of curing a portion of the layer
(ca) in a state in which the particles (a2) are buried in the layer
obtained by combining the layer (ca) and the layer (b) between the
step (4) and the step (5).
3. The method of manufacturing a laminate according to claim 2,
wherein, in the step (2), the portion of the layer (a) is cured by
irradiation with ultraviolet rays at an irradiation amount of 1 to
90 ml/cm.sup.2, to obtain the layer (ca).
4. The method of manufacturing a laminate according to claim 1,
wherein, in the step (2), the portion of the layer (a) is cured by
irradiation with ultraviolet rays at an irradiation amount of 1 to
90 mJ/cm.sup.2, to obtain the layer (ca).
5. A method of manufacturing an antireflection film, comprising, in
this order: manufacturing the laminate according to claim 1; a step
(6) of bonding the layer (ca) to a substrate; a step (7) of curing
the layer (ca) in a state in which the particles (a2) are buried in
the layer obtained by combining the layer (ca) and the layer (b);
and a step (8) of peeling the pressure sensitive film.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a laminate, a method of
manufacturing a laminate, and a method of manufacturing an
antireflection film.
2. Description of the Related Art
In an image display device such as a display device using a cathode
ray tube (CRT), a plasma display panel (PDP), an electroluminescent
display (ELD), a vacuum fluorescent display (VFD), a field emission
display (FED), and a liquid crystal display device (LCD), an
antireflection film may be provided in order to prevent decrease in
contrast due to reflection of external light on a display surface
and reflected glare of an image. In addition to the image display
device, the antireflection function may be provided to a glass
surface of the showroom or the like by an antireflection film.
As the antireflection film, an antireflection film having a fine
uneven shape with a period equal to or less than the wavelength of
visible light on the surface of a substrate, that is, an
antireflection film having a so-called moth eye structure is known.
The moth eye structure makes a refractive index gradient layer in
which the refractive index successively changes in a pseudo manner
from the air toward the bulk material inside the substrate, and
reflection of the light can be prevented.
Further, as a technique for forming a functional layer in an
optical film, a technique (transfer method) using a transfer member
for forming a functional layer is known.
JP2016-095498A discloses a transfer member comprising a peeling
substrate, mesoporous silica nanoparticles buried in a single layer
and a removable state on the surface of the peeling substrate, and
an antireflection member using the above transfer member.
JP2012-086475A discloses a thin film transfer material comprising a
temporary support and fine particles lamination film formed on the
surface of the temporary support.
SUMMARY OF THE INVENTION
However, the present inventors conducted research to find that, in
the techniques of JP2016-095498A and JP2012-086475A, it was not
possible to form an antireflection film having a low haze and a
sufficient antireflection function.
An object of the present invention is to provide a laminate capable
of being used in order to manufacture an antireflection film by a
transfer method and manufacturing an antireflection film having a
low haze and satisfactory antireflection properties, a method of
manufacturing the laminate, and a method of manufacturing an
antireflection film using the laminate.
The present inventors have assumed that it was not possible to form
an antireflection film having a low haze because, as in the
transfer members disclosed in JP2016-095498A and JP2012-086475A, in
a case where particles in the transfer member are exposed to the
air, an attractive force (horizontal capillary force) derived from
surface tension works, to aggregate particles, and have conducted
research to obtain an antireflection film having a low haze and
satisfactory antireflection properties by using a transfer member
(laminate) without exposure of the particles to the air.
That is, the present inventors have found that the above object can
be achieved by the following means.
<1> A laminate comprising: a support; a layer (b) including a
pressure sensitive adhesive; particles (a2) having an average
primary particle diameter of 100 nm to 380 nm and a layer (ca)
including a resin,
in which the layer (b) is provided closer to the support than the
layer (ca),
the particles (a2) are buried in a layer obtained by combining the
layer (b) and the layer (ca), and protrudes from an interface of
the layer (ca) on the support side, and
a portion including the particles (a2) and the layer (ca) is
peelable from the layer (b).
<2> The laminate according to <1>, in which a value
obtained by subtracting a haze of a portion obtained by removing
the portion including the particles (a2) and the layer (ca) from
the laminate from the total haze of the laminate is 1.00% or
less.
<3> The laminate according to <1> or <2>, in
which a surface roughness of a surface of the layer (ca) on an
opposite side to the layer (b) is 30 nm or less.
<4> The laminate according to any one of <1> to
<3>, further comprising: a peelable member on a surface of
the layer (ca) on an opposite side to the layer (b).
<5> A method of manufacturing a laminate, comprising, in this
order: a step (1) of providing particles (a2) having an average
primary particle diameter of 100 nm to 380 nm and a curable
compound (a1) on a temporary support in a thickness in which the
particles (a2) are buried in a layer (a) including the curable
compound (a1);
a step (2) of curing a portion of the layer (a) to obtain a layer
(ca):
a step (3) of bonding a layer (b) of a pressure sensitive film
having a support and the layer (b) including a pressure sensitive
adhesive on the support, to the layer (ca);
a step (4) of causing a position of an interface of the layer (ca)
on the support side to come close to the temporary support side
such that the particles (a2) are buried in a layer obtained by
combining the layer (ca) and the layer (b) and protrudes from the
interface of the layer (ca) on the support side; and
a step (5) of peeling the temporary support.
<6> The method of manufacturing a laminate according to claim
5, further comprising: a step (4-2) of curing a portion of the
layer (ca) in a state in which the particles (a2) are buried in a
layer obtained by combining the layer (ca) and the layer (b)
between the step (4) and the step (5).
<7> The method of manufacturing a laminate according to
<5> or <6>, in which, in the step (2), the portion of
the layer (a) is cured by irradiation with ultraviolet rays at an
irradiation amount of 1 to 90 mJ/cm.sup.2, to obtain the layer
(ca).
<8> A method of manufacturing an antireflection film using
the laminate obtained by the method of manufacturing a laminate
according to any one of <5> to <7>.
<9> The method of manufacturing an antireflection film
according to <8>, comprising, in this order: a step (6) of
bonding a layer (ca) of a laminate obtained by the method of
manufacturing a laminate according to any one of <5> to
<7> to a substrate:
a step (7) of curing the layer (ca) in a state in which the
particles (a2) are buried in a layer obtained by combining the
layer (ca) and a layer (b); and
a step (8) of peeling the pressure sensitive film.
According to the present invention, a laminate which can be used to
manufacture an antireflection film by a transfer method and can
manufacture an antireflection film having a low haze and
satisfactory antireflection properties, a method of manufacturing
the laminate, and a method of manufacturing an antireflection
film.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view for describing an example of a method of
manufacturing a laminate according to the embodiment of the present
invention.
FIG. 2 is a schematic view for describing an example of a method of
manufacturing an antireflection film according to the embodiment of
the present invention.
FIG. 3 is a schematic cross-sectional view illustrating an example
of an antireflection film manufactured by the manufacturing method
according to the embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the present specification, "(meth)acrylate" refers to at least
one of acrylate or methacrylate, "(meth)acryl" refers to at least
one of acryl or methacryl, and "(meth)acryloyl" refers to at least
one of acryloyl or methacryloyl.
The laminate according to the embodiment of the present invention
is a laminate having a support, a layer (b) including a pressure
sensitive adhesive, particles (a2) having an average primary
particle diameter of 100 nm to 380 nm, and a layer (ca) including a
resin, in which the layer (b) is provided closer to the support
than the layer (ca), the particles (a2) is buried in a layer
obtained by combining the layer (b) and the layer (ca) and
protrudes from an interface on the support side of the layer (ca),
and a portion including the particles (a2) and the layer (ca) is
peeled off from the layer (b).
Since a portion of the laminate according to the embodiment of the
present invention which includes the particles (a2) and the layer
(ca) can be peeled off from the layer (b), a portion
(antireflection layer) including the particles (a2) and the layer
(ca) in the laminate according to the embodiment of the present
invention can be transferred to a substrate by a transfer method by
using the laminate according to the embodiment of the present
invention, so as to manufacture the antireflection film.
Accordingly, the laminate according to the embodiment of the
present invention can be used as a transfer member for forming an
antireflection layer.
Detailed descriptions of the laminate according to the embodiment
of the present invention are described below, and the method of
manufacturing the laminate and the method of manufacturing an
antireflection film according to the embodiment of the present
invention are described below.
[Method of Manufacturing Laminate and Method of Manufacturing
Antireflection Film]
The method of manufacturing the laminate according to the
embodiment of the present invention has a step (1) of providing the
particles (a2) having an average primary particle diameter of 100
nm to 380 nm and a curable compound (a1) on a temporary support in
a thickness in which the particles (a2) is buried in the layer (a)
including the curable compound (a1), a step (2) of curing a portion
of the layer (a) so as to obtain the layer (ca), a step (3) of
bonding the support and the layer (b) of the pressure sensitive
film having the layer (b) including the pressure sensitive adhesive
on the support to the layer (ca), and a step (4) of causing a
position of an interface of the layer (ca) on the support side to
come close to the temporary support side, such that the particles
(a2) are buried in a layer obtained by combining the layer (ca) and
the layer (b), so as to protrude from the interface of the layer
(ca) on the support side, and a step (5) of peeling the temporary
support, in this order.
The method of manufacturing the laminate according to the
embodiment of the present invention preferably has a step (4-2) of
curing the portion of the layer (ca) in a state in which the
particles (a2) are buried in a layer obtained by combining the
layer (ca) and the layer (b), between the step (4) and the step
(5).
The method of manufacturing the antireflection film according to
the embodiment of the present invention is preferably a method of
manufacturing an antireflection film using the laminate obtained by
the method of manufacturing the laminate according to the
embodiment of the present invention, and has a step (6) of bonding
the layer (ca) of the laminate obtained by the method of
manufacturing the laminate according to the embodiment of the
present invention and the substrate, a step (7) of curing the layer
(ca) in a state in which the particles (a2) are buried in the layer
obtained by combining the layer (ca) and the layer (b), a step (8)
of peeling the pressure sensitive film, in this order.
The method of manufacturing the antireflection film according to
the embodiment of the present invention more preferably has a step
(9) of curing the layer (ca) in a state in which the particles (a2)
protrude from an interface of the layer (ca) on an opposite side to
the interface on the substrate side after the step (8), and a step
(10) of washing a solvent, in this order.
In the present invention, the expression "the particles (a2) are
buried in the layer (a)" means that the thickness of the layer (a)
is 0.8 times or more of the average primary particle diameter of
the particles (a2).
According to the present invention, the expression "the particles
(a2) are buried in the layer obtained by combining the layer (ca)
and the layer (b)" indicates that the thickness of the layer
obtained by combining the layer (ca) and the layer (b) is 0.8 times
or more of the average primary particle diameter of the particles
(a2).
In the present invention, in the step (1), in order to form the
layer (a) in a thickness in which the particles (a2) are buried, in
steps subsequent to the step (4), a surface of the particles (a2)
protruding from the layer (ca) is coated with a thin layer of the
layer (ca). The particles (a2) coated with the thin layer is called
the particles (a2) for the sake of convenience.
First, an outline of an embodiment of the method of manufacturing
the laminate according to the embodiment of the present invention
is described with reference to FIG. 1.
FIG. 1 is a schematic view illustrating a preferable embodiment of
the method of manufacturing a laminate according to the embodiment
of the present invention.
(1) of FIG. 1 schematically illustrates a state in which the
particles (a2) (reference numeral 3 in FIG. 1) having an average
primary particle diameter of 100 nm to 380 nm in the layer (a)
(reference numeral 4 in FIG. 1) including the curable compound (a1)
is provided on a temporary support 1 in the step (1) in a thickness
in which the particles (a2) are buried.
(2) of FIG. 1 schematically illustrates a case where a portion of
the layer (a) is cured in a state in which the particles (a2) are
buried in the layer (a) in the step (2). The layer (ca) is obtained
by curing a portion of the layer (a). In FIGS. 1 and 2, both of the
layer (a) and the layer (ca) are represented by the same reference
numeral 4, for the sake of convenience. "UV" represents ultraviolet
rays.
(3) of FIG. 1 schematically illustrates a state in which the layer
(b) of the pressure sensitive film 7 having a support 5 and a layer
(b) (reference numeral 6 in FIG. 1) including a pressure sensitive
adhesive on the support 5 is bonded to the layer (ca) (reference
numeral 4 in FIG. 1) in the step (3).
(4) of FIG. 1 schematically illustrates a state in which a position
of an interface of the layer (ca) on the support side is caused to
come close to the temporary support side, such that the particles
(a2) are buried in a layer obtained by combining the layer (ca) and
the layer (b) and protrude from the interface (the interface of the
layer (ca) and the layer (b)) of the layer (ca) on the support
side, in the step (4). As described above, examples of the method
of causing the position of the interface of the layer (ca) on the
support side to come close to the temporary support side include a
method of causing a portion of the curable compound (a1) to
permeate the temporary support (in a case where the temporary
support has a functional layer, to permeate the functional layer)
or a method of causing a portion of the curable compound (a1) to
permeate the layer (b) including a pressure sensitive adhesive.
(4-2) of FIG. 1 schematically illustrates a case where a portion of
the layer (ca) is further cured in a state in which the particles
(a2) are buried in a layer obtained by combining the layer (ca) and
the layer (b) in the step (4-2).
(5) of FIG. 1 illustrates a state (a laminate 8) after the
temporary support 1 is peeled off in the step (6) of peeling off
the temporary support 1.
The step (5) is completed so as to obtain the laminate 8. Here, in
the method of manufacturing the laminate according to the
embodiment of the present invention, the step (4-2) is not
necessary, and thus after the step (4), the step (5) may be
performed after the step (4-2) is performed.
Subsequently, an outline of an embodiment of the method of
manufacturing the antireflection film according to the embodiment
of the present invention is described with reference to FIG. 2.
FIG. 2 is a schematic view illustrating a preferable embodiment of
the method of manufacturing an antireflection film according to the
embodiment of the present invention.
(6) of FIG. 2 schematically illustrates a state in which a
substrate 9 is bonded to the layer (ca) (reference numeral 4 in
FIG. 2) in the laminate 8 in the step (6).
(7) of FIG. 2 schematically illustrates a case where the layer (ca)
is further cured in a state in which the particles (a2) are buried
in a layer obtained by combining the layer (ca) and the layer (b)
in the step (7).
(8) of FIG. 2 schematically illustrates a state after the pressure
sensitive film 7 is peeled off in the step (8) of peeling off the
pressure sensitive film 7. The step (8) is a step of peeling off
the pressure sensitive film 7 from the laminate 8 and transferring
a portion (reference numeral 2 in FIG. 2) including the particles
(a2) (reference numeral 3 in FIG. 2) and the layer (ca) (reference
numeral 4 in FIG. 2) in the laminate 8 to the substrate 9. A
portion including the particles (a2) and the layer (ca) forms a
moth eye structure in which the particles (a2) protrude from one
surface of the layer (ca). That is, a portion including the
particles (a2) and the layer (ca) is an antireflection layer. By
the step (8), it is possible to obtain an antireflection film 10
having an antireflection layer having a moth eye structure
including the particles (a2) and the layer (ca) on the substrate.
In a stage in which the step (8) is completed, the antireflection
film 10 can be obtained, but it is preferable to further perform
the steps (9) and (10).
(9) of FIG. 2 schematically illustrates that the layer (ca) is
further cured in a state in which the particles (a2) protrude from
the interface of the layer (ca) on an opposite side to the
interface on the substrate side in the step (9).
(10) of FIG. 2 illustrates the antireflection film 10 in a state
after solvent washing is performed in the step (10).
Hereinafter, each step of the method of manufacturing the laminate
and the method of manufacturing an antireflection film according to
the embodiment of the present invention is specifically
described.
[Step (1)]
The step (1) is a step of providing the curable compound (a1) and
the particles (a2) having an average primary particle diameter of
100 nm to 380 nm on the temporary support, in a thickness in which
the particles (a2) are buried in the layer (a) including the
curable compound (a1).
As described above, according to the present invention, the
expression "a thickness in which the particles (a2) are buried in
the layer (a)" refers to a thickness of 0.8 times or more of an
average primary particle diameter of the particles (a2).
In the step (1), a method of providing the layer (a) on the
temporary support is not particularly limited, but it is preferable
to provide the layer (a) by coating the temporary support with the
layer (a). In this case, the layer (a) is a layer obtained by
applying a composition for forming the layer (a) including the
curable compound (a1) and the particles (a2) having an average
primary particle diameter of 100 nm to 380 nm. The coating method
is not particularly limited, and well-known methods can be used.
Examples thereof include a dip coating method, an air knife coating
method, a curtain coating method, a roller coating method, a wire
bar coating method, a gravure coating method, and a die coating
method.
In the layer (a) provided on the temporary support in the step (1),
it is preferable that the plurality of particles (a2) are present
in the direction orthogonal to the surface of the layer (a). Here,
the expression "the plurality of particles (a2) are not present in
the direction orthogonal to the surface of the layer (a)" indicates
that, in a case where 10 .mu.m.times.10 .mu.m of the in-plane of
the layer (a) is observed with three visual fields with a scanning
electron microscope (SEM), the proportion of the number of
particles (a2) in a state in which a plurality of the particles are
not present in the direction orthogonal to the surface is 80% or
more and preferably 95% or more.
(Temporary Support)
The temporary support is not particularly limited as long as the
support has a smooth surface. It is preferable that the temporary
support has a surface flatness with a surface roughness of about 30
nm or less and does not prevent the application of the composition
for forming the layer (a), and temporary supports including various
materials can be used, but for example, a polyethylene
terephthalate (PET) film or a cycloolefin-based resin film is
preferably used.
In the present invention, the surface roughness is measured by
using SPA-400 (manufactured by Hitachi High-Tech Science
Corporation) under measurement conditions of a measurement range of
5 .mu.m.times.5 .mu.m, a measurement mode of DFM, and a measurement
frequency of 2 Hz.
(Layer (a))
The layer (a) is a layer including the curable compound (a1).
The curable compound (a1) included in the layer (a) is cured to
become a resin (binder resin) in the antireflection layer.
The film thickness of the layer (a) in the step (1) is preferably
0.8 times to 2.0 times, more preferably 0.8 times to 1.5 times, and
even more preferably 0.9 times to 1.2 times of an average primary
particle diameter of the particles (a2).
<Curable Compound (A1)>
The curable compound (a1) is preferably a compound (preferably an
ionizing radiation curable compound) having a polymerizable
functional group. As the compound having a polymerizable functional
group, various monomer oligomers, and polymers can be used. As the
polymerizable functional group (polymerizable group),
photopolymerizable, electron beam polymerizable, or radiation
polymerizable groups are preferable. Among the groups, a
photopolymerizable functional group is preferable.
Examples of the photopolymerizable functional group include a
polymerizable unsaturated group (carbon-carbon unsaturated double
bond group) such as a (meth)acryloyl group, a vinyl group, a styryl
group, and an allyl group. Among the groups, a (meth)acryloyl group
is preferable.
Specific examples of the compound having a polymerizable
unsaturated group include (meth)acrylic acid diesters of alkylene
glycol such as neopentyl glycol acrylate, 1,6-hexanediol
(meth)acrylate, and propylene glycol di(meth)acrylate;
(meth)acrylic acid diesters of polyoxyalkylene glycol such as
triethylene glycol di(meth)acrylate, dipropylene glycol
di(meth)acrylate, polyethylene glycol di(meth)acrylate, and
polypropylene glycol di(meth)acrylate;
(meth)acrylic acid diesters of polyhydric alcohol such as
pentaerythritol di(meth)acrylate; and
(meth)acrylic acid diesters of an ethylene oxide or propylene oxide
adduct such as 2,2-bis{4-(acryloxy.diethoxy)phenyl} propane, and
2-2-bis{4-(acryloxy.polypropoxy)phenyl} propane.
Epoxy (meth)acrylates, urethane (meth)acrylates, and polyester
(meth)acrylates are also preferably used as a compound having a
photopolymerizable functional group.
Among these, esters of polyhydric alcohol and (meth)acrylic acid
are preferable. More preferably, it contains at least one
polyfunctional monomer having three or more (meth)acryloyl groups
in one molecule.
Examples thereof include pentaerythritol tetra(meth)acrylate,
pentaerythritol tri(meth)acrylate, trimethylolpropane
tri(meth)acrylate, ethylene oxide (EO)-modified trimethylolpropane
tri(meth)acrylate, propylene oxide (PO)-modified trimethylolpropane
tri(meth)acrylate, EO-modified phosphate tri(meth)acrylate,
trimethylol ethane tri(meth)acrylate, ditrimethylolpropane
tetra(meth)acrvlate, dipentaerythritol tetra(meth)acrylate,
dipentaerythritol penta (meth)acrylate, dipentaerythritol
hexa(meth)acrylate, pentaerythritol hexa(meth)acrylate,
1,2,3-cyclohexane tetramethacrylate, polyurethane polyacrylate,
polyester polyacrylate, and caprolactone-modified
tris(acryloxyethyl) isocyanurate.
Specific compounds of polyfunctional acrylate-based compounds
having (meth)acryloyl groups include esterified products of polyol
and (meth)acrylic acid such as KAYARAD DPHA, KAYARAD DPHA-2C,
KAYARAD PET-30, KAYARAD TMPTA, KAYARAD TPA-320, KAYARAD TPA-330,
KAYARAD RP-1040, KAYARAD T-1420, KAYARAD D-310, KAYARAD DPCA-20.
KAYARAD DPCA-30, KAYARAD DPCA-60, and KAYARAD GPO-303 manufactured
by Nippon Kayaku Co. Ltd., and V #3PA. V #400, V #36095D. V #1000,
and V #1080 manufactured by Osaka Organic Chemical Industry Ltd. A
trifunctional or higher functional urethane acrylate compound such
as SHIKOH UV-1400B, SHIKOH UV-1700B, SHIKOH UV-6300B, SHIKOH
UV-7550B, SHIKOH UV-7600B, SHIKOH UV-7605B, SHIKOH UV-7610B, SHIKOH
UV-7620EA, SHIKOH UV-7630B, SHIKOH UV-7640B, SHIKOH UV-6630B,
SHIKOH UV-7000B, SHIKOH UV-7510B, SHIKOH UV-7461TE, SHIKOH
UV-3000B. SHIKOH UV-3200B, SHIKOH UV-3210EA, SHIKOH UV-3310EA,
SHIKOH UV-3310B. SHIKOH UV-3500BA, SHIKOH UV-3520TL, SHIKOH
UV-3700B, SHIKOH UV-6100B, SHIKOH UV-6640B, SHIKOH UV-2000B, SHIKOH
UV-2010B, SHIKOH UV-2250EA, and SHIKOH UV-2750B (manufactured by
Nippon Synthetic Chem Industry Co., Ltd.), UA-306 H, UA-306 I,
UA-306 T, and UL-503 LN (manufactured by Kyoeisha Chemical Co.,
Ltd.), UNIDIC 17-806, UNIDIC 17-813, UNIDIC V-4030, and UNIDIC
V-4000BA (manufactured by DIC Corporation), EB-1290K. EB-220,
EB-5129, EB-1830, and EB-4858 (manufactured by Daicel-UCB
Corporation), U-4HA, U-6HA, U-10HA, and U-15HA (manufactured by
Shin Nakamura Chemical Co., Ltd.), HIGH-COAP AU-2010 and HIGH-COAP
AU-2020 (manufactured by Tokushiki Co., Ltd.), ARONIX M-1960
(manufactured by Toagosei Co., Ltd.), ARTRESIN UN-3320HA,
UN-3320HC, UN-3320HS, UN-904, and HDP-4T (manufactured by Negami
Chemical Industrial Co., Ltd.), trifunctional or higher functional
polyester compounds such as ARONIX M-8100. M-8030, and M-9050
(manufactured by Toagosei Co., Ltd.), and KRM-8307 (manufactured by
Daicel-Allnex Ltd.) can be suitably used.
Examples thereof include a resin having three or more polymerizable
functional groups, for example, a polyester resin having a
relatively low molecular weight, a polyether resin, an acrylic
resin, an epoxy resin, an urethane resin, an alkyd resin, a
spiroacetal resin, a polybutadiene resin, and a polythiol polyene
resin, or an oligomer or a prepolymer of a polyfunctional compound
such as polyhydric alcohol.
Compounds disclosed in JP2005-076005A and JP2005-036105A,
dendrimers such as SIRIUS-501 and SUBARU-501 (manufactured by Osaka
Organic Chemical Industry Ltd.), and norbomene ring-containing
monomers disclosed in JP2005-060425A can be used.
In order to obtain a strong film by bonding the particles (a2) and
the curable compound (a1) to each other, a silane coupling agent
having a polymerizable functional group may be used as the curable
compound (a1).
Specific examples of a silane coupling agent having a polymerizable
functional group include 3-(meth)acryloxypropyltrimethoxysilane,
3-(meth)acryloxypropy Imethyldimethoxysilane,
3-(meth)acryloxypropyldimethylmethoxysilane,
3-(meth)acryloxypropylmethyldiethoxysilane, 3-(meth)acryloxypropyl
triethoxysilane, 2-(meth)acryloxyethyltrimethoxysilane,
2-(meth)acryloxvethyltriethoxysilane,
4-(meth)acryloxybutyltrimethoxvsilane, and
4-(meth)acyloxybutyltriethoxysilane. Specific examples thereof
include KBM-503 and KBM-5103 (manufactured by Shin-Etsu Chemical
Co., Ltd.), silane coupling agents X-12-1048, X-12-1049, and
X-12-1050 (manufactured by Shin-Etsu Chemical Co., Ltd.) disclosed
in JP2014-123091A, and a compound C3 represented by the following
structural formula.
##STR00001##
As a compound working so as to suppress the aggregation of the
particles (a2), a silane coupling agent which has polymerizable
functional groups other than a radical reactive group may be used.
Specific examples of the silane coupling agent which has
polymerizable functional groups other than a radical reactive group
include KBM-303, KBM-402, KBM-403, KBE-402. KBE-403, and KBM-4803
(manufactured by Shin-Etsu Chemical Co., Ltd.).
Two or more types of the compounds having a polymerizable
functional group may be used in combination. The polymerization of
these compounds having a polymerizable functional group can be
performed by irradiation with ionizing radiation or heating under
the presence of a photo-radical initiator or a thermal radical
initiator.
The layer (a) can further include a compound in addition to the
curable compound (a1).
According to the present invention, as the curable compound (a1), a
compound having two or less polymerizable functional groups in one
molecule may be used. Particularly, it is preferable that the
compound having three or more polymerizable functional groups in
one molecule and a compound having two or less polymerizable
functional groups in one molecule or a compound not having a
polymerizable functional group as a compound other than the curable
compound (a1) are used in combination.
The compound having two or more polymerizable functional groups in
one molecule or a compound not having a polymerizable functional
group is preferably a compound in which a weight-average molecular
weight Mwa is 40<Mwa<500.
The compound having two or less polymerizable functional groups in
one molecule is preferably a compound having one polymerizable
functional group in one molecule.
The viscosity of the compound having two or more polymerizable
functional groups in one molecule or the compound not having a
polymerizable functional group at 25.degree. C. is preferably 100
mPas or less and more preferably 1 to 50 mPas. The compound in this
viscosity range is preferable since the compound works so as to
suppress aggregation of the particles (a2) such that haze and
muddiness can be suppressed.
The compound having two or less polymerizable functional groups in
one molecule preferably has a (meth)acryloyl group, an epoxy group,
an alkoxy group, a vinyl group, a styryl group, and an allyl group
as the polymerizable functional group.
As the compound not having a polymerizable functional group, an
ester-based compound, an amine-based compound, an ether-based
compound, an aliphatic alcohol-based compound, a hydrocarbon-based
compound, and the like can be preferably used, and an ester-based
compound is particularly preferable. More specific examples thereof
include dimethyl succinate (viscosity 2.6 mPas), diethyl succinate
(viscosity 2.6 mPas), dimethyl adipate (viscosity 2.8 mPas),
dibutyl succinate (viscosity: 3.9 mPas), bis(2-butoxyethyl) adipate
(viscosity 10.8 mPas), dimethyl suberate (viscosity: 3.7 mPas),
diethyl phthalate (viscosity: 9.8 mPas), dibutyl phthalate
(viscosity: 13.7 mPas), triethyl citrate (viscosity: 22.6 mPas),
acetyl triethyl citrate (viscosity: 29.7 mPas), and diphenyl ether
(viscosity: 3.8 mPas).
The weight-average molecular weight and the number-average
molecular weight according to the present invention are a value
measured in the following conditions by the gel permeation
chromatography (GPC).
[Solvent] Tetrahydrofuran
[Device Name] TOSOH HLC-8220GPC
[Column] Three items of TOSOH TSKgel Super HZM-H
(4.6 mm.times.15 cm) are linked to be used.
[Column temperature] 25.degree. C.
[Sample concentration] 0.1 mass %
[Flow rate] 0.35 ml/min
[Calibration Curve] A calibration curve with seven samples of TSK
standard polystyrene manufactured by TOSOH Corporation Mw=2,800,000
to 1,050 is used.
The coating amount of the curable compound (a1) included in the
layer (a) is preferably 100 mg/m.sup.2 to 800 mg/m.sup.2, more
preferably 100 mg/m.sup.2 to 600 mg/m, and particularly preferably
100 mg/m.sup.2 to 400 mg/m.sup.2.
In a case where the curable compound (a1) and a compound not having
a polymerizable functional group are used in combination, the total
coating amount thereof is preferably in the above range.
<Particles (a2) having an average primary particle diameter of
100 nm to 380 nm>
The particles (a2) having an average primary particle diameter of
100 nm to 380 nm is referred to as the "particles (a2)".
The particles (a2) are particles protruding from the surface of the
film (the layer (ca)) formed of the binder resin in the
antireflection film and having an uneven shape (moth eye
structure).
Examples of the particles (a2) include metal oxide particles, resin
particles, and organic-inorganic hybrid particles having a core of
a metal oxide particle and a shell of a resin. In view of excellent
film hardness, the metal oxide particles are preferable.
Examples of the metal oxide particles include silica particles,
titania particles, zirconia particles, and antimony pentoxide
particles. Since the refractive index is close to many binders,
haze is hardly generated and the moth eye structure is easily
formed. Therefore, silica particles are preferable.
Examples of the resin particles include polymethyl methacrylate
particles, polystyrene particles, and melamine particles.
In view of forming a moth eye structure by arranging particles side
by side, the average primary particle diameter of the particles
(a2) is 100 nm to 380 nm, preferably 100) nm to 300) nm, more
preferably 150 nm to 250 nm, and even more preferably 170 nm to 220
nm.
Only one kind of the particles (a2) may be used singly, or two or
more kinds of particles having different average primary particle
diameters may be used.
The average primary particle diameter of the particles (a2) refers
to the cumulative 50% particle diameter of the volume-average
particle diameter. A scanning electron microscope (SEM) can be used
to measure the particle diameter. A powder particle (in a case of a
dispersion liquid, ones obtained by volatilizing a solvent by
drying) is observed at the appropriate magnification (about 5000
times) by scanning electron microscope (SEM) observe, the diameter
of each of 100 primary particles is measured, the volume thereof is
calculated, and the cumulative 50% particle diameter can be taken
as the average primary particle diameter. In a case where the
particles are not spherical, the average value of the long diameter
and the short diameter is regarded as the diameter of the primary
particle. In a case where the particles contained in the
antireflection film are measured, it is calculated by observing the
antireflection film from the front surface side by SEM in the same
manner as described above. In this case, for easier observation,
carbon vapor deposition, an etching treatment, and the like may be
suitably applied to the sample.
A shape of the particle (a2) is most preferably a spherical shape,
but may be a shape other than a spherical shape such as an
amorphous shape.
The particles (a2) may be solid particles or may be hollow
particles, but is preferably solid particles.
The silica particles may be crystalline or amorphous.
As the particles (a2), surface-treated inorganic fine particles are
preferably used for improving the dispersibility in the coating
solution, improving the film hardness, and preventing aggregation.
Specific examples and preferable examples of the surface treatment
method are in the same manner as those described in <0119> to
<0147> of JP2007-298974A.
Particularly, in view of providing the binding properties to the
curable compound (a1) which is a binder component and improving the
film hardness, it is preferable that the surface of the particle is
surface-modified with a compound having a functional group having
reactivity with an unsaturated double bond and the particle
surface, and an unsaturated double bond is applied to the particle
surface. As the compound used in the surface modification, a silane
coupling agent having a polymerizable functional group described
above as the curable compound (a1) can be appropriately used.
Specific examples of the particles having an average primary
particle diameter of 10) nm to 380 nm include SEAHOSTAR KE-P10
(average primary particle diameter: 100 nm, amorphous silica
manufactured by Nippon Shokubai Co. Ltd.), SEAHOSTAR KE-P30
(average primary particle diameter: 300 nm, amorphous silica
manufactured by Nippon Shokubai Co., Ltd.), SEAHOSTAR KE-S30
(average primary particle diameter: 300 nm, heat resistance:
1,000.degree. C., calcined silica manufactured by Nippon Shokubai
Co., Ltd.), EPOSTAR S (average primary particle diameter: 200 nm, a
melamine-formaldehyde condensate manufactured by Nippon Shokubai
Co., Ltd.), EPOSTAR MA-MX100W (average primary particle diameter:
175 nm, polymethylmethacrylate (PMMA) crosslinked product
manufactured by Nippon Shokubai Co., Ltd.), EPOSTAR MA-MX200W
(average primary particle diameter: 350 nm, polymethylmethacrylate
(PMMA) crosslinked product manufactured by Nippon Shokubai Co.,
Ltd.), STAFYROID (multilayer structure organic fine particles
manufactured by Aica Kogyo Company, Limited), and GANZPEARL
(polymethyl methacrylate, polystyrene particles manufactured by
Aica Kogyo Company, Limited) can be preferably used.
Since the amount of hydroxyl groups on the surface is moderately
large and the particles are hard, the particles (a2) are
particularly preferably calcined silica particles.
The calcined silica particles can be manufactured by a well-known
technique of hydrolyzing and condensing a hydrolyzable silicon
compound in an organic solvent including water and a catalyst to
obtain silica particles and calcining the silica particles, and,
for example, JP2003-176121A and JP2008-137854A can be referred
to.
The silicon compound as a raw material for manufacturing the
calcined silica particles is not particularly limited, and examples
thereof include a chlorosilane compound such as tetrachlorosilane,
methyltrichlorosilane, phenyltrichlorosilane,
dimethyldichlorosilane, diphenyldichlorosilane, methyl vinyl
dichlorosilane, trimethylchlorosilane, and methyl
diphenylchlorosilane; an alkoxy silane compound such as
tetramethoxy silane, tetraethoxy silane, tetraisopropoxy silane,
tetrabutoxy silane, methyltrimethoxy silane, methyltriethoxy
silane, trimethoxyvinyl silane, triethoxyvinyl silane,
3-glycidoxypropyltrimethoxy silane, 3-chloropropyltrimethoxy
silane, 3-mercaptopropyltrimethoxy silane, 3-(2-aminoethylamino)
propyltrimethoxy silane, phenyltrimethoxy silane, phenyltriethoxy
silane, dimethyl dimethoxy silane, dimethyl diethoxy silane,
3-glycidoxypropylmethyldimethoxy silane,
3-glycidoxypropylmethyldiethoxy silane,
3-chloropropylmethyldimethoxy silane, diphenyldimethoxy silane,
diphenyldiethoxy silane, dimethoxydiethoxy silane, trimethylmethoxy
silane, and trimethylethoxy silane; an acyloxy silane compound such
as tetraacetoxy silane, methyl triacetoxy silane, phenyl triacetoxy
silane, dimethyl diacetoxy silane, diphenyl diacetoxy silane, and
trimethylacetoxy silane; and a silanol compound such as dimethyl
silanediol, diphenyl silanediol, and trimethylsilanol. Among the
exemplary silane compounds, an alkoxysilane compound is
particularly preferable, since alkoxysilane compound can be
obtained more easily and halogen atoms as impurities in the
obtained calcined silica particles are not included. As a preferred
embodiment of the calcined silica particles according to the
present invention, it is preferable that the content of halogen
atoms is substantially 0%, and halogen atoms are not detected.
The calcining temperature is not particularly limited, but is
preferably 800.degree. C. to 1,300.degree. C. and more preferably
1,000.degree. C. to 1,200.degree. C.
The coating amount of the curable compound (a2) included in the
layer (a) is preferably 50 mgim.sup.2 to 200 mg/m.sup.2, more
preferably 100 mg/m.sup.2 to 180 mg/m.sup.2, and particularly
preferably 130 mg/m.sup.2 to 170 mg/m. In a case where the coating
amount is the lower limit or more, a large number of protrusions of
the moth eye structure can be formed, and thus the antireflection
performance are more easily improved. In a case where the coating
amount is the upper limit or less, aggregation in the liquid hardly
occurs and a satisfactory moth eye structure is easily formed.
It is preferable that only one kind of the monodispersed silica
fine particles having an average primary particle diameter of 100
nm to 380 nm and having a dispersion degree (CV value) of the
particle diameter of less than 5% is contained, since the height of
the unevenness of the moth eye structure becomes homogeneous and
the reflectivity is further decreased. The CV value is usually
measured using a laser diffraction type particle diameter
determination device, but other particle diameter measuring methods
may be used, or particle size distribution can be calculated and
obtained from the surface SEM image of the antireflection layer of
the present invention by image analysis. The CV value is more
preferably less than 4%.
The layer (a) may contain a component in addition to the curable
compound (a1) and the particles (a2), and examples thereof include
the compound not having a polymerizable functional group, a
solvent, a polymerization initiator, a dispersing agent of the
particles (a2), a leveling agent, and an antifouling agent.
<Solvent>
In view of improving the dispersibility, it is preferable to select
a solvent having a polarity close to that of the particles (a2).
Specifically, for example, in a case where the particles (a2) are
metal oxide particles, an alcohol-based solvent is preferable, and
examples thereof include methanol, ethanol, 2-propanol, 1-propanol,
and butanol. For example, in a case where the particles (a2) are
metal resin particles subjected to hydrophobic surface
modification, ketone-based, ester-based, carbonate-based, alkane,
aromatic solvents, and the like are preferable, and examples
thereof include methyl ethyl ketone (MEK), dimethyl carbonate,
methyl acetate, acetone, methylene chloride, and cyclohexanone. A
plurality of these solvents may be mixed to be used without
remarkably deteriorating the dispersibility.
<Dispersing agent of particles (a2)>
The dispersing agent of the particles (a2) lowers the cohesive
force between the particles such that the particles (a2) can be
easily arranged in a uniform manner. The dispersing agent is not
particularly limited, but an anionic compound such as sulfuric acid
salt and phosphoric acid salt, a cationic compound such as
aliphatic amine salt and quaternary ammonium salt, a nonionic
compound, and a polymer compound are preferable, and a polymer
compound is more preferable since the polymer compound has a high
degree of freedom in selecting adsorptive groups and steric
repulsive groups. As the dispersing agent, a commercially available
product can be used. Examples thereof include DISPERBYK160,
DISPERBYK161, DISPERBYK162, DISPERBYK163, DISPERBYK164,
DISPERBYK166, DISPERBYK167, DISPERBYK171. DISPERBYK180,
DISPERBYK182, DISPERBYK2000, DISPERBYK2001, DISPERBYK2164, Bykumen,
BYK-2009, BYK-P104, BYK-P104S, BYK-220S, Anti-Terra203,
Anti-Terra204, and Anti-Terra205 (all are trade names) manufactured
by BYK Japan KK.
<Leveling Agent>
The leveling agent lowers the surface tension of the composition
for forming the layer (a), such that the liquid after coating is
stabilized and the curable compound (a1) and the particles (a2) are
easily arranged in a uniform manner. For example, compounds
disclosed in JP2004-331812A and JP2004-163610A can be used.
The content of the leveling agent is preferably 0.01 to 5.0 mass %,
more preferably 0.01 to 3.0 mass %, and particularly preferably
0.01 to 2.0 mass % with respect to the total solid content of the
composition for forming the layer (a).
<Antifouling Agent>
The antifouling agent provides water and oil repelling properties
to the moth eye structure, such that adhesion of dirt and
fingerprints can be suppressed. For example, compounds disclosed in
JP2012-88699A can be used.
The content of the antifouling agent is preferably 0.01 to 5.0 mass
%, more preferably 0.01 to 3.0 mass %, and particularly preferably
0.01 to 2.0 mass % with respect to the total solid content of the
antifouling agent in the layer (a).
<Polymerization Initiator>
A polymerization initiator may be used in the layer (a).
In a case where the curable compound (a1) is a photopolymerizable
compound, it is preferable to include a photopolymerization
initiator.
Examples of the photopolymerization initiator include
acetophenones, benzoins, benzophenones, phosphine oxides, ketals,
anthraquinones, thioxanthones, an azo compound, peroxides,
2,3-dialkyldione compounds, disulfide compounds, fluoroamine
compounds, aromatic sulfoniums, lophine dimers, onium salts, borate
salts, active esters, active halogens, an inorganic complex, and
coumarins. Specific examples, preferable aspects, commercially
available products and the like of the photopolymerization
initiator are disclosed in paragraphs<0133> to <0151>
of JP2009-098658A and can be appropriately used in the present
invention in the same manner.
Various examples are provided in "Newest UV curing technology"
{Technical Information Institute Co. Ltd.} (1991), page 159 and
"Ultraviolet Curing System" written by Kiyomi KATO (published in
1989 by The Integrated Technology Center), pages 65 to 148, and are
useful in the present invention.
The content of the polymerization initiator in the layer (a) is an
amount sufficient for polymerizing the polymerizable compound
included in the layer (a) and is preferably 0.1 to 8 mass % and
more preferably 0.5 to 5 mass % with respect to the total solid
content in the layer (a) such that the starting point does not
excessively increase.
For the reaction of the silane coupling agent described above, a
compound that generates an acid or a base by light or heat
(hereinafter, sometimes referred to as a photoacid generator, a
photobase generator, a thermal acid generator, or a thermal base
generator) may be included.
<Photoacid Generator>
Examples of the photoacid generator include onium salt such as
diazonium salt, ammonium salt, phosphonium salt, iodonium salt,
sulfonium salt, selenonium salt, and an arsonium salt, an
organohalogen compound, organometallic/organic halide, a photoacid
generator having an o-nitrobenzyl-based protecting group, a
compound that is photolyzed to generate sulfonic acid and is
represented by iminosulfonate and the like, a disulfone compound,
diazoketosulfone, and a diazodisulfone compound. Examples thereof
also include triazines (for example,
2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, and
the like), quaternary ammonium salts, a diazomethane compound, an
imide sulfonate compound, and an oxime sulfonate compound.
A group that generates an acid by light or a compound obtained by
introducing a compound into a main chain or a side chain of a
polymer can be used.
Compounds that generate acid by light which are disclosed in V. N.
R Pillai, Synthesis, (1), 1 (1980), A. Abad et al., Tetrahedron
Lett., (47) 4555 (1971). D. H. R. Barton et al., J. Chem. Soc.,
(C), 329 (1970), U.S. Pat. No. 3,779,778A, and EP126,712B can be
used.
<Thermal Acid Generator>
Examples of the thermal acid generator include salt including an
acid and an organic base.
Examples of the acid described above include organic acid such as
sulfonic acid, phosphonic acid, and carboxylic acid and inorganic
acid such as sulfuric acid and phosphoric acid. In view of
compatibility with the curable compound (a1), organic acid is more
preferable, sulfonic acid and phosphonic acid are more preferable,
and sulfonic acid is particularly preferable. Preferable examples
of sulfonic acid include p-toluenesulfonic acid (PTS),
benzenesulfonic acid (BS), p-dodecylbenzenesulfonic acid (DBS),
p-chlorobenzenesulfonic acid (CBS), 1,4-naphthalenedisulfonic acid
(NDS), methanesulfonic acid (MsOH), and nonafluorobutane-1-sulfonic
acid (NFBS).
As specific examples of the acid generator, acid generators
disclosed in JP2016-000803A can be appropriately used.
<Photobase Generator>
Examples of the photobase generator include a substance that
generates bases by the action of active energy rays. More
specifically, (1) a salt of organic acid and a base which is
decomposed by decarburization by irradiation with ultraviolet rays,
visible light, or infrared rays, (2) a compound decomposed by
intramolecular nucleophilic substitution reaction or dislocation
reaction to emit amines, or (3) a substance which causes some
chemical reaction by irradiation with ultraviolet rays, visible
light, or infrared rays to emit a base can be used.
The photobase generator used in the present invention is not
particularly limited, as long as the photobase generator is a
substance that generates a base by the action of active energy rays
such as ultraviolet rays, electron beams, X-rays, infrared rays,
and visible light.
Specifically, photobase generators disclosed in JP2010-243773A can
be appropriately used.
The content of the compound that generates an acid or a base by
light or heat in the layer (a) is an amount sufficient for
polymerizing the polymerizable compound included in the layer (a)
and is preferably 0.1 to 8 mass % and more preferably 0.1 to 5 mass
% with respect to the total solid content in the layer (a) such
that the starting point does not excessively increase.
[Step (2)]
The step (2) is a step of curing a part of the layer (a) in the
step (1) to obtain a layer (ca), specifically, curing a portion of
the curable compound (a1) in the layer (a) of the step (1) to
obtain the layer (ca) including the cured compound (a1c).
In a case where a portion of the curable compound (a1) is cured in
the step (2), the particles (a2) are caused to hardly move such
that the aggregation of the particles (a2) can be suppressed.
The expression "a portion of the curable compound (a1) is cured"
means that not the entire curable compound (a1) is cured, but only
a portion thereof is cured. By a method of curing only a portion of
the curable compound (a1) in the step (2), causing a portion of the
uncured curable compound (a1) to permeat (permeat to a functional
layer in a case where the temporary support has the functional
layer) a temporary support in the step (4) or a method of causing
permeation to the layer (b), the thickness of the layer (ca) is
reduced so as to cause the particles (a2) to protrude from the
interface of the layer (ca) on the support side, such that a
satisfactory unevenness shape (moth eye structure) can be
formed.
The curing can be performed by irradiation with ionizing radiation.
The kind of ionizing radiation is not particularly limited, and
examples thereof include X-rays, electron beams, ultraviolet rays,
visible light, infrared rays, but the curable compound (a1) is a
photocurable compound, and it is preferable to cure a portion of
the curable compound (a1) by irradiation with light (preferably
ultraviolet light) in the step (2).
In a case where the temporary support is coated with the
composition excluding the particles (a2) from the composition for
forming the layer (a) in a thickness of 2 .mu.m and the composition
is cured, the condition of curing a portion of the curable compound
(a1) in the step (2) is preferably a condition in which a curing
rate becomes 2% to 20%, more preferably a condition in which a
curing rate becomes 3% to 15%, and even more preferably a condition
in which a curing rate becomes 5% to 12%.
The curing rate is obtained from the following expression. (1-the
number of residual polymerizable functional groups after curing/the
number of polymerizable functional groups before curing).times.100%
The polymerizable functional group is a group having a
polymerizable carbon-carbon unsaturated double bond. The curing
rate is measured in the following method.
Specifically, NICOLET6700 Fourier transform infrared
spectrophotometer (FT-IR) of Thermo electron corporation is used,
KBr-IR of the curable compound before curing is measured, a peak
(1,660-1,800 cm.sup.-1) area of the carbonyl group and a peak
height (808 cm.sup.-1) of the polymerizable carbon-carbon
unsaturated double bond are determined, a peak of the polymerizable
carbon-carbon unsaturated double bond with respect to the carbonyl
group peak area is obtained in the same manner as in the infrared
spectroscopy (IR) measurement of single reflection after curing,
and peaks before and after ultraviolet ray irradiation are
compared, so as to calculate the curing rate. Here, with respect to
the calculation of the curing rate, the measured depth at 808
cm.sup.-1 is regulated as 821 nm, and the depth at 1660-1800
cm.sup.-1 is regulated as 384 nm.
In the step (2), the ultraviolet ray is preferably applied in the
irradiation amount of 1 to 90 mJ/cm.sup.2, more preferably applied
in the irradiation amount of 1.2 to 40 mJ/cm.sup.2, and even more
preferably applied in the irradiation amount of 1.5 to 10
mJ/cm.sup.2. The optimum value of the irradiation amount varies
depending on the formulation of the composition for forming the
layer (a), and can be appropriately adjusted.
In the step (2), it is preferable that a portion of the curable
compound (a1) is cured by irradiation with the ultraviolet ray from
the opposite to the temporary support side of the substrate, in
view of manufacturing suitability.
It is preferable that the step (2) is performed in the environment
of the oxygen concentration of 0.1 to 5.0 volume %, and it is more
preferable that the step (2) is performed in the environment of the
oxygen concentration of 0.5 to 1.0 volume %. In a case where the
oxygen concentration is caused to be in the above range,
particularly, the region on the temporary support side of the layer
(a) can be cured.
The compound (a1c) is a cured product of the curable compound
(a1).
The molecular weight of the compound (a1c) is not particularly
limited. The compound (a1c) may have an unreacted polymerizable
functional group.
The layer (ca) obtained in the step (2) is a layer including the
curable compound (a1) and the compound (a1c) in the layer.
In the present invention, after the step (2), in the steps (4-2),
(7), and (9), the layer (ca) can be further cured, components
contained in each layer and formulation (formulation ratios of the
curable compound (a1) and the compound (a1c) which is a cured
product thereof) thereof are different before curing and after
curing in each step, but in the present invention, the layer is
called the layer (ca) in any steps, for the sake of
convenience.
[Step (3)]
A step (3) is a step of bonding a layer (b) of a pressure sensitive
film having a support and the layer (b) including a pressure
sensitive adhesive on the support to the layer (ca).
The method of bonding the layer (ca) and the layer (b) of the
pressure sensitive film is not particularly limited, and well-known
methods may be used. Examples thereof include a lamination
method.
It is preferable to bond a pressure sensitive film such that the
layer (ca) and the layer (b) are in contact with each other.
Before the step (3), a step of drying the layer (ca) may be
provided. In a case of having a step of drying the layer (ca), the
drying temperature of the layer (ca) is preferably 20.degree. C. to
60.degree. C. and more preferably 20.degree. C. to 40.degree. C.
The drying time is preferably 0.1 to 120 seconds and more
preferably 1 to 30 seconds.
According to the present invention, the layer (b) of the pressure
sensitive film and the layer (ca) are bonded to each other in the
step (3), the particles (a2) are buried in the layer obtained by
combining the layer (ca) and the layer (b) in the step (4), the
particles (a2) are caused to protrude from the interface of the
layer (ca) on the support side, or it is more preferable that a
portion of the layer (ca) is further cured in a state in which the
particles (a2) are buried in the layer obtained by combining the
layer (ca) and the layer (b) in the step (4-2) described below,
such that the particles (a2) are not exposed to an air interface of
the layer (ca) before curing, and aggregation is suppressed, so as
to manufacture a satisfactory uneven shape formed by the particles
(a2).
(Pressure Sensitive Film)
The pressure sensitive film has a support and the layer (b)
including a pressure sensitive adhesive.
<Layer (b)>
The layer (b) is a layer of including a pressure sensitive
adhesive, and the pressure sensitive adhesive is preferably a
pressure sensitive adhesive having a gel fraction of 95.0% or
more.
In a case where a gel fraction of the pressure sensitive adhesive
is 95.0% or more, in the manufacturing of the antireflection film
according to the embodiment of the present invention, in a case of
peeling the pressure sensitive film, the pressure sensitive
adhesive component hardly remains on the antireflection film
surface, and thus an effect of suppressing the increase of the
reflectivity caused by the filling of portions between unevenness
of the particles with the pressure sensitive adhesive component is
high.
The gel fraction of the pressure sensitive adhesive is preferably
in the range of 95.0% to 99.9%, more preferably in the range of
97.0% to 99.9%, and even more preferably in the range of 98.0% to
99.9%.
The gel fraction of the pressure sensitive adhesive is a proportion
of an insoluble matter after the pressure sensitive adhesive is
immersed in tetrahydrofuran (THF) at 25.degree. C. for 12 hours and
is obtained from the following expression. Gel fraction=(mass of
insoluble matter of pressure sensitive adhesive in THF)/(total mass
of pressure sensitive adhesive).times.100(%)
The weight-average molecular weight of the sol component in the
pressure sensitive adhesive is preferably 10.000 or less, more
preferably 7,000 or less, and particularly preferably 5,000 or
less. By setting the weight-average molecular weight of the sol
component within the above range, in the manufacturing of an
antireflection film according to the embodiment of the present
invention, in a case of peeling the pressure sensitive film, the
component of the pressure sensitive adhesive can be caused to
hardly remain on the antireflection film surface.
The sol component of the pressure sensitive adhesive represents a
dissolution amount in THF after the pressure sensitive adhesive is
immersed in tetrahydrofuran (THF) at 25.degree. C. for 12 hours.
The weight-average molecular weight can be analyzed by gel
permeation chromatography (GPC).
It is also preferable that a storage modulus of elasticity (G') of
the pressure sensitive adhesive at 30.degree. C. and 1 Hz is 1.3
GPa or less, and the weight-average molecular weight of the sol
component in the pressure sensitive adhesive is 10,000 or less.
It is also preferable that a storage modulus of elasticity (G') of
the pressure sensitive adhesive at 30.degree. C. and 1 Hz is
1.3.times.10.sup.5 Pa or less, and the weight-average molecular
weight of the sol component in the pressure sensitive adhesive is
10,000 or less.
The storage modulus of elasticity (G') of the pressure sensitive
adhesive at 30.degree. C. and 1 Hz is more preferably 0.1.times.10'
Pa to 1.3.times.10' Pa and even more preferably 0.1.times.10.sup.5
Pa to 1.2.times.10' Pa. In a case where the storage modulus of
elasticity is 0.1.times.10' Pa or more, aggregation fracture of the
pressure sensitive adhesive hardly occurs and handling is easy. In
a case where the storage modulus of elasticity is 1.3.times.10' Pa
or less, the pressure sensitive adhesive easily enters the gaps
between the particles, and thus an effect of suppressing of
aggregation of the particles may be easily obtained. Therefore, in
a case where the storage modulus of elasticity is
1.2.times.10.sup.5 Pa or less, it is possible to obtain the
antireflection film having a satisfactory reflectivity.
The preferable range of the weight-average molecular weight of the
sol component in the pressure sensitive adhesive in this case is as
described above.
The film thickness of the layer (b) is preferably 0.1 .mu.m to 50
.mu.m, more preferably 1 .mu.m to 30 .mu.m, and even more
preferably 1 .mu.m to 20 .mu.m.
The pressure sensitive adhesive preferably includes a polymer and
more preferably includes a (meth)acrylic polymer. Particularly, a
polymer (in a case where two or more kinds of monomers, a
copolymer) of at least one monomer of (meth)acrylic acid alkyl
ester monomers having an alkyl group of 1 to 18 carbon atoms is
preferable. The weight-average molecular weight of the
(meth)acrylic polymer is preferably 200,000 to 2,000,000.
Examples of the (meth)acrylic acid alkyl ester monomer in which an
alkyl group has 1 to 18 carbon atoms include an alkyl
(meth)acrylate monomer such as methyl (meth)acrvlate, ethyl
(meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate,
isobutyl (meth)acrylate, pentyl (meth)acrylate, hexyl
(meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate,
isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl
(meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate,
cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, isomyristyl
(meth)acrylate, isocetyl (meth)acrylate, isostearyl (meth)acrylate,
myristyl (meth)acrylate, cetyl (meth)acrylate, stearyl
(meth)acrylate, tetradecyl (meth)acrylate, pentadecyl
(meth)acrylate, hexadecyl (meth)acrylate, heptadecyl
(meth)acrylate, and octadecyl (meth)acrylate. The alkyl group of
the alkyl (meth)acrylate monomer may be linear, branched or cyclic.
Two or more of the monomers may be used in combination.
Preferable examples of the (meth)acrylate monomer having an
aliphatic ring include cyclopentyl (meth)acrylate, cyclohexyl
(meth)acrylate, cycloheptyl (meth)acrylate, and isobornyl
(meth)acrylate. Among these, cyclohexyl (meth)acrylate is
particularly preferable.
The (meth)acrylic polymer is a copolymer including at least one of
(meth)acrylic acid alkyl ester monomers having an alkyl group of 1
to 18 carbon atoms and at least one of other copolymerizable
monomers. In this case, examples of the other copolymerizable
monomers include a copolymerizable vinyl monomer containing at
least one group selected from a hydroxyl group, a carboxyl group,
and an amino group, a copolymerizable vinyl monomer having a vinyl
group, and an aromatic monomer.
Examples of the copolymerizable vinyl monomer containing a hydroxyl
group include hydroxyl group-containing (meth)acrylate esters such
as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate,
3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate,
6-hydroxyhexyl (meth)acrylate, and 8-hydroxyoctyl (meth)acrylate,
and hydroxyl group-containing (meth)acrylamides such as N-hydroxy
(meth)acrylamide, N-hydroxymethyl (meth)acrylamide, and
N-hydroxyethyl (meth)acrylamide, and the copolymerizable vinyl
monomer is preferably at least one selected from the group of these
compounds.
It is preferable that the content of the copolymerizable vinyl
monomer containing a hydroxyl group is 0.1 to 15 parts by mass with
respect to 100 parts by mass of the (meth)acrylic polymer.
Examples of the copolymerizable vinyl monomer containing a carboxyl
group include (meth)acrylic acid, itaconic acid, crotonic acid,
maleic acid, fumaric acid, carboxyethyl (meth)acrylate, and
carboxypentyl (meth)acrylate, and at least one selected from the
group of these compounds is preferable.
The content of the copolymerizable vinyl monomer containing a
carboxyl group is preferably 0.1 to 2 parts by mass with respect to
100 parts by mass of the (meth) acrylic copolymer.
Examples of the copolymerizable vinyl monomer containing an amino
group include monoalkylaminoalkyl (meth)acrylate such as
monomethylaminoethyl (meth)acrylate, monoethylaminoethyl
(meth)acrylate, monomethyl aminopropyl (meth)acrylate, and
monoethylaminopropyl (meth)acrylate.
Examples of the aromatic monomer include styrene in addition to
aromatic group-containing (meth)acrylate esters such as benzyl
(meth)acrylate and phenoxyethyl (meth)acrylate.
Examples of the copolymerizable vinyl monomer other than the above
include various vinyl monomers such as acrylamide, acrylonitrile,
methyl vinyl ether, ethyl vinyl ether, vinyl acetate, and vinyl
chloride.
The pressure sensitive adhesive may include a cured product of a
composition (also referred to as a pressure sensitive adhesive
composition) for forming the pressure sensitive adhesive.
The pressure sensitive adhesive composition preferably includes the
polymer and the crosslinking agent, and may be crosslinked by heat,
ultraviolet rays (UV), or the like. The crosslinking agent is
preferably one or more crosslinking agents selected from a compound
group consisting of a difunctional or higher functional
isocyanate-based crosslinking agent, a difunctional or higher
functional epoxy-based crosslinking agent, and an aluminum
chelate-based crosslinking agent. In a case where a crosslinking
agent is used, in the manufacturing the antireflection film
according to the embodiment of the present invention, in view of
causing the pressure sensitive adhesive component to hardly remain
on the antireflection film surface, the content of the crosslinking
agent is preferably 0.1 to 15 parts by mass, more preferably 3.5 to
15 parts by mass, even more preferably more than 3.5 parts by mass
and less than 15 parts by mass, and particularly preferably 5.1 to
10 parts by mass with respect to 100 parts by mass of the
polymer.
The difunctional or higher functional isocyanate-based compound may
be a polyisocyanate compound having at least two isocyanate (NCO)
groups in one molecule, and examples thereof include a
burette-modified product and an isocyanurate-modified product of
diisocyanates (compounds having two NCO groups in one molecule)
such as hexamethylene diisocyanate, isophorone diisocyanate,
diphenylmethane diisocyanate, tolylene diisocyanate, and xylylene
diisocyanate, and an adduct (polyol modified product) with
trivalent or higher valent polyols (compounds having at least three
OH groups in one molecule) such as trimethylolpropane and
glycerin.
A trifunctional or higher functional isocyanate-based compound is a
polyisocyanate compound having at least three or more isocyanate
(NCO) groups in one molecule, and particularly at least one or more
selected from the compound group consisting of an isocyanurate body
of a hexamethylene diisocyanate compound, an isocyanurate body of
an isophorone diisocyanate compound, an adduct of hexamethylene
diisocyanate compound, an adduct of isophorone diisocyanate
compound, a burette body of a hexamethylene diisocyanate compound,
and a burette body of an isophorone diisocyanate compound are
preferable.
The difunctional or higher functional isocyanate-based crosslinking
agent is contained in an amount of preferably 0.01 to 5.0 parts by
mass and more preferably 0.02 to 3.0 parts by mass, with respect to
100 parts by mass of the polymer.
The pressure sensitive adhesive composition may contain an
antistatic agent in order to provide antistatic performances. The
antistatic agent is preferably an ionic compound and more
preferably quaternary onium salt.
As the antistatic agent which is a quatemary onium salt, for
example, an alkyldimethylbenzyl ammonium salt having an alkyl group
having 8 to 18 carbon atoms, a dialkylmethylbenzyl ammonium salt
having an alkyl group having 8 to 18 carbon atoms, a trialkylbenzyl
ammonium salt having an alkyl group having 8 to 18 carbon atoms, a
tetraalkyl ammonium salt having an alkyl group having 8 to 18
carbon atoms, an alkyldimethylbenzyl phosphonium salt having an
alkyl group having 8 to 18 carbon atoms, a dialkylmethylbenzyl
phosphonium salt having an alkyl group having 8 to 18 carbon atoms,
a trialkylbenzyl phosphonium salt having an alkyl group having 8 to
18 carbon atoms, a tetraalkyl phosphonium salt having an alkyl
group having 8 to 18 carbon atoms, an alkyl trimethyl ammonium salt
having an alkyl group having 14 to 20 carbon atoms, and an
alkyldimethyl ethyl ammonium salt having an alkyl group having 14
to 20 carbon atoms can be used. These alkyl groups may be alkenyl
groups having an unsaturated bond.
As the antistatic agent, in addition to the above, nonionic,
cationic, anionic, and amphoteric surfactants, ionic liquid, alkali
metal salt, metal oxide, metal fine particles, a conductive
polymer, carbon, a carbon nanotube can be used.
Examples of the alkali metal salt include metal salt including
lithium, sodium, and potassium. In order to stabilize ionic
substances, a compound containing a polyoxyalkylene structure may
be added.
The antistatic agent preferably contains 0.1 to 10 parts by mass
with respect to 100 parts by mass of the polymer.
The pressure sensitive adhesive composition can further contain a
polyether-modified siloxane compound having HLB of 7 to 15 as an
antistatic aid.
HLB is a hydrophilic-lipophilic balance (hydrophilic lipophilicity
ratio) defined, for example, by JIS (Japanese Industrial Standard)
K3211 (surfactant term) and the like.
The pressure sensitive adhesive composition can further contain a
crosslinking accelerator. In a case where a polyisocyanate compound
is used as a crosslinking agent, the crosslinking accelerator may
be a substance, functioning as a catalyst for the reaction
(crosslinking reaction) between the copolymer and the crosslinking
agent, and examples thereof include an amine-based compound such as
tertiary amine, and an organometallic compound such as a metal
chelate compound, an organotin compounds, an organic lead compound,
organozinc compound. According to the present invention, the
crosslinking accelerator is preferably a metal chelate compound or
an organotin compound.
The content of the crosslinking accelerator is preferably 0.001 to
0.5 parts by mass with respect to 100 parts by mass of the
copolymer.
It is preferable that, the laminate of the present invention has
three or more crosslinking groups in one molecule on the surface of
the layer (b) of the layer (ca) side, a crosslinking group
equivalent is 450 or less, and a lubricant (hereinafter also
referred to as a "lubricant a") having a low friction portion
consisting of fluorine or silicone is present.
In a case where the lubricant a is present on the surface of the
layer (b) on the layer (ca) side, in the manufacturing of the
antireflection film according to the embodiment of the present
invention, it is possible to effectively prevent the pressure
sensitive adhesive in the layer (b) from remaining on (transferred
to) the surface of the antireflection film.
<Support>
The support in the pressure sensitive film is described.
As the support, a plastic film formed of a resin having
transparency and flexibility is preferably used. Preferable
examples of the plastic film for the support include a film formed
of a polyester film such as polyethylene terephthalate,
polyethylene naphthalate, polyethylene isophthalate, and
polybutylene terephthalate, a (meth)acrylic resin, a
polycarbonate-based resin, a polystyrene-based resin, a
polyolefin-based resin, a cyclic polyolefin-based resin, and a
cellulose-based resin such as cellulose acylate. Here, the
(meth)acrylic resin is preferably a polymer having a lactone ring
structure, a polymer having a glutaric anhydride ring structure,
and a polymer having a glutarimide ring structure.
Other plastic films can be used as long as the plastic films have
required strength and optical suitability. The support may be an
unstretched film or may be uniaxially or biaxially stretched.
Otherwise, the support may be a plastic film in which an angle of
the axis method formed according to the stretching ratio and
stretching crystallization is controlled.
As the support, those having ultraviolet permeability are
preferable. It is preferable to have ultraviolet permeability in
view of manufacturing suitability, since in the steps (4-2) and
(7), ultraviolet irradiation from the support side can be performed
in a case of curing the layer (ca).
Specifically, the maximum transmittance of the support at the
wavelength of 250 nm to 300 nm is preferably 20% or more, more
preferably 40% or more, and particularly preferably 60% or more. It
is preferable that the maximum transmittance at the wavelength of
250 nm to 300 nm is 20% or more, since the layer (ca) can be easily
cured by being irradiated with ultraviolet rays from the support
side.
Specifically, the maximum transmittance of the pressure sensitive
film in which the layer (b) is formed on the support at the
wavelength of 250 nm to 300 nm is preferably 20% or more, more
preferably 40% or more, and particularly preferably 60% or
more.
The film thickness of the support is not particularly limited, but
is preferably 10 .mu.m to 100 .mu.m, more preferably 10 .mu.m to 50
.mu.m, and even more preferably 10 .mu.m to 40 .mu.m.
As the pressure sensitive film obtained by forming the layer (b) on
the support, a commercially available protective film can be
suitably used. Specific examples thereof include AS3-304, AS3-305,
AS3-306, AS3-307, AS3-310, AS3-04421, AS3-0520, AS3-0620, LBO-307,
NBO-0424, ZBO-0421, S-362, and TFB-4T3-367AS manufactured by
Fujimori Kogyo Co., Ltd.
In the steps (4-2) and (7), the layer (ca) is cured while a state
in which the particles (a2) are buried in the layer obtained by
combining the layer (ca) and the layer (b) is maintained, but in
the stage before the step (4-2) (that is, after the step (4) is
completed), it is preferable to have an uneven shape formed by the
particles (a2) protruding from the interface of the layer (ca) on
the support side. In this manner, in a case where the layer (b) is
peeled off in the step (8) after the layer (ca) is cured in the
step (7), it is possible to obtain the antireflection film in a
state in which the particles (a2) protrude on the surface of the
layer (a).
In the stage before the step (4-2), in order to provide an uneven
shape formed by the particles (a2) protruding from the interface of
the layer (ca) on the support side, in the step (4), it is
preferable to cause a portion of the curable compound (a1) to
permeate the layer (b).
[Step (4)]
The step (4) is a step of burying the particles (a2) in the layer
obtained by combining the layer (ca) and the layer (b) and causing
a position of the interface (preferably an interface of the layer
(ca) and the layer (b)) of the layer (ca) on the support side to be
close to the temporary support side so as to protrude from the
interface of the layer (ca) on the support side.
The expression "burying the particles (a2) in the layer obtained by
combining the layer (ca) and the layer (b) and protruding from the
interface of the layer (ca) on the support side" is, in other
words, "causing the particles (a2) not to be exposed from the layer
obtained by combining the layer (ca) and the layer (b) and to be
present across both layers of the layer (ca) and the layer (b) (the
particles (a2) are present across the interface between the layer
(ca) and the layer (b))".
It is preferable that the step (4) is performed by causing a
portion of the curable compound (a1) to permeate the layer (b).
In step (4), in a case where a portion of compound (a1) is caused
to permeate the layer (b), the laminate after the step (3) is
completed is maintained preferably at less than 60.degree. C. and
more preferably at 40.degree. C. or less. By maintaining the
temperature at 40.degree. C. or less, the viscosity of the curable
compound (a1), the compound (a1c), and pressure sensitive adhesive
can be maintained to be high, and at the same time, the thermal
motion of the particles (a2) can be suppressed, and thus has a high
effect of suppressing the decrease of the antireflection
performances due to aggregation of the particles (a2) and the
increase of the haze or the muddiness. The lower limit of the
temperature at which the laminate is maintained is not particularly
limited, and may be the room temperature or a temperature lower
than the room temperature.
[Step (4-2)]
The step (4-2) is a step of curing a portion of the layer (ca) in a
state in which the particles (a2) are buried in the layer obtained
by combining the layer (ca) and the layer (b), and specifically,
curing a portion of the compound selected from the group consisting
of the curable compound (a1) and the compound (a1c) in the layer
(ca).
Curing a portion of the layer (ca) refers to curing only a portion,
not all of the curable compound (a1) and the compound (a1c) in the
layer (ca). Accordingly, it is possible to form a binder resin in
the antireflection layer of the antireflection film. By causing the
uncured curable compound (a1) to remain in the layer (ca) after the
completion of the step (4-2), in the step (6) described below,
bonding and adhesion between the layer (ca) and the substrate
becomes possible.
In the step (4-2), since a state in which the particles (a2) are
buried in the layer obtained by combining the layer (ca) and the
layer (b) is maintained, the aggregation of the particles (a2) are
suppressed and the moth eye structure can be formed.
In a case where it is considered that the state in which the
particles (a2) are buried in the layer obtained by combining the
layer (ca) and the layer (b) cannot be maintained due to the
volatilization of the component of the layer (b) or the layer (ca)
after the layer (b) is provided, an operation of thickening the
layer (b) in advance or the like can be performed.
In the step (4-2), the curing can be performed by irradiation with
ionizing radiation. The kind of ionizing radiation is not
particularly limited, and examples thereof include X-rays, electron
beams, ultraviolet rays, visible light, and infrared rays. However,
ultraviolet light is widely used. For example, in a case where the
coating film is ultraviolet curable, it is preferable that a
portion of the curable compound (a1) in the layer (ca) is cured by
being irradiated with ultraviolet rays in an irradiation amount of
10 mJ/cm.sup.2 to 1,000 mJ/cm.sup.2 by an ultraviolet lamp. In a
case where the irradiation amount of the ultraviolet rays is 10
mJ/cm.sup.2 or more, the adhesion force between the layer (b) and a
portion including the particles (a2) and the layer (ca) becomes
appropriately strong, the particles (a2) and the layer (ca) hardly
remains on the temporary support in the step (5) of peeling the
temporary support, and defects (regions in which the reflectivity
decreases) are less likely to occur in the obtained antireflection
film. In a case where the irradiation amount of the ultraviolet
rays is 1,000 mJ/cm.sup.2 or less, a residual amount of the curable
compound (a1) in the layer (ca) after the completion of the step
(4-2) does not decrease too much, and an appropriate adhesion force
between the layer (ca) and the substrate in the step (6) can be
obtained. The irradiation amount in the step (4-2) is not
particularly limited, and can be appropriately adjusted considering
the adhesion force between the used layer (b) and the used portion
including the particles (a2) and the layer (ca) and the adhesion
force between the layer (ca) and the substrate. At the time of
irradiation, the energy may be applied at once or can be applied in
a divided manner. As the ultraviolet lamp type, a metal halide
lamp, a high pressure mercury lamp, or the like is suitably
used.
The oxygen concentration at the curing in the step (4-2) is
preferably 0 to 1.0 vol %, more preferably 0 to 0.1 vol %, and
particularly preferably 0 to 0.05 vol %. In a case where the oxygen
concentration at curing is smaller than 1.0 vol %, curing
inhibition caused by oxygen is hardly received, and the film
becomes strong.
In the step (4-2), in a case where the portion of the compound
selected from the group consisting of the curable compound (a1) and
the compound (a1c) in the layer (ca) is cured, the layer (ca) side
of the support may be irradiated with ultraviolet rays from the
opposite side or may be irradiated with ultraviolet rays from the
temporary support side.
[Step (5)]
The step (5) is a step of peeling the temporary support from the
laminate after the completion of the step (4) or (4-2).
In order to peel off the temporary support from the laminate after
the completion of the step (4) or (4-2), it is preferable that
appropriately adhesion force is applied between the layer (ca) and
the temporary support, and a portion (which is a portion including
the particles (a2) represented by reference numeral 3 and the layer
(ca) represented by reference numeral 4 in FIG. 1, and a portion
corresponding to the antireflection layer 2 of FIG. 2) including
the layer (ca) and the particles (a2) is in a state of being
capable of being transferred to the pressure sensitive film. For
example, a portion including the layer (ca) and the particles (a2)
is not detached from the temporary support in the bending or
transport tension of the laminate during the manufacturing process,
but, it is preferable that, in a case of being brought into contact
with the layer (b) or in a case of being brought into contact with
the layer (b) and performing ultraviolet radiation, a portion
including the layer (ca) and the particles (a2) is detached.
A laminate obtained completing the step (5) is a laminate of the
present invention.
In the steps (2), (3), (4), (4-2), and (5), it is preferable that a
plurality of particles (a2) are not present in a direction
orthogonal to the surface of the layer (ca).
Here, the expression "the plurality of particles (a2) are not
present in the direction orthogonal to the surface of the layer
(ca)" indicates that, in a case where 10 .mu.m.times.10 .mu.m of
the in-plane of the layer (ca) is observed with three visual fields
with a scanning electron microscope (SEM), the proportion of the
number of particles (a2) in a state in which a plurality of the
particles are not present in the direction orthogonal to the
surface is 80% or more and preferably 95% or more.
In steps (4), (4-2), and (5), the total film thickness of the layer
(ca) and the layer (b) is preferably more than the average primary
particle diameter of the particles (a2).
It is preferable that the total film thickness of the film
thickness of the layer (ca) and the film thickness of the layer (b)
is more than the average primary particle diameter of the particles
(a2), since it is possible to cause the particles (a2) to be buried
in the layer obtained by combining the layer (ca) and the layer
(b).
In the steps (4), (4-2), and (5), the film thickness of the layer
(ca) is preferably 5% to 70% and more preferably 20% to 40% of the
average primary particle diameter of the particles (a2). It is
preferable that the film thickness of the layer (ca) is 5% or more
of the average primary particle diameter of the particles (a2),
since the particles (a2) are hardly separated from the
antireflection film that can be obtained after the pressure
sensitive film is peeled off in the step (8) described below, and
the portion including the layer (ca) and the particles (a2) is
transferred to the substrate, and the scratch resistance is
improved. In a case where the film thickness of the layer (ca) is
70% or less of the average primary particle diameter of the
particles (a2), the inclination of the refractive index is
sufficient, and sufficient antireflection properties can be
obtained. It is preferable that the film thickness of the layer
(ca) is 20% to 40% of the average primary particle diameter of the
particles (a2), since both of the sufficient scratch resistance and
the sufficient antireflection performance can be obtained. The same
is applied in the steps (6) to (10) below.
It is preferable that the film thickness of the layer (ca) after
the completion of the step (5) is adjusted so as to be 10 nm to 100
nm (more preferably 20 nm to 90 nm and even more preferably 30 nm
to 70 nm) in a case where a film cross section of the layer (ca) is
observed, with a scanning electron microscope (SEM), and film
thicknesses at any 100 portions are measured, and the average value
thereof is obtained.
It is preferable that in the layer (b) side of the layer (ca) in
the laminate which can be obtained by the completion of the step
(5), the particles (a2) do not protrude from the surface on the
opposite side.
The surface roughness of the surface of the layer (ca) on the
opposite side to the layer (b) in the laminate which can be
obtained by the completion of the step (5) is preferably 30 nm or
less and more preferably 10 nm or less.
In a case where the surface roughness of the surface of the layer
(ca) on the opposite side to the layer (b) is 30 nm or less, the
particles (a2) do not protrude from the surface of the layer (ca)
on the opposite side to the layer (b), and in a case where the
pressure sensitive film is peeled off in the step (8) described
below and a portion (antireflection layer) including the layer (ca)
and the particles (a2) is transferred to the substrate, the portion
is easily transferred, and defects are generated on the
antireflection layer after the transfer. It is preferable that the
surface roughness of the surface of the layer (ca) on the opposite
side of the layer (b) is 10 nm or less, since, in a case where the
layer (ca) and the substrate are bonded to each other in the step
(6), satisfactory adhesive can be secured, and the generation of
cavities between the transferring layer (the portion including the
particles (a2) and the layer (ca)) and the substrate which occurs
the increase of the haze of the antireflection film can be
suppressed.
In the present invention, the surface roughness is measured by
SPA-400 (manufactured by Hitachi High-Tech Science Corporation)
under measurement conditions of a measurement range 5 .mu.m.times.5
.mu.m, a measurement mode of DFM, and a measurement frequency of 2
Hz.
The portion including the particle (a2) and the layer (ca) in the
laminate which can be obtained by the completion of the step (5) is
peeled off from the layer (b) of the pressure sensitive film.
The fact that the portion including the particles (a2) and the
layer (ca) can be peeled off from the layer (b) of the pressure
sensitive film means that, an adhesion force is appropriately
applied between the portion including the particles (a2) and the
layer (ca) and the layer (b) of the pressure sensitive film, and
thus a portion including the particles (a2) and the layer (ca) in
the transferring step (the step (8)) described below is in a state
of being detached from the surface of the layer (b) and transferred
to the substrate surface. The fact that the portion (antireflection
layer) including the particles (a2) and the layer (ca) can be
transferred to the substrate surface, that is, has transferability
means that, in a case where a black polyethylene terephthalate
sheet with a pressure sensitive adhesive (manufactured by Tomoegawa
Co., Ltd.; "clearly seen") is bonded to an opposite side to the
transfer surface (a surface having an antireflection layer) of the
transferred antireflection film and is visually observed, a
proportion of an region in which reflectivity decreases more than
that before an antireflection layer is transferred is 80% or more
with respect to the transferred area. The adhesion force between
the portion including the particles (a2) and the layer (ca) and the
layer (b) is not particularly limited, but, for example, the
adhesion force can be measured by an adhesion force in a case where
the portion including the particles (a2) of the transfer member
(the laminate that can be obtained by the completion of the step
(5)) having a width of 25 mm and the layer (ca) is fixed to a glass
substrate having a thickness of 1.1 mm by using an adhesive, and
the portion including the particles (a2) and the layer (ca) and the
layer (b) are peeled off from each other in the 90.degree.
direction and the speed of 1,000 mm/min. It is preferable that the
peeling force measured by the method is preferably 0.2 N/25 mm to
4.0 N/25 mm and more preferably 0.6 N/25 mm to 4.0 N/25 mm. In a
case where the peeling force is 0.6 N/25 mm or more, in the step
(5), in a case where the temporary support is peeled off, the
portion of the particles (a2) and the layer (ca) hardly remains on
the temporary support, and thus the reflectivity of the finally
obtained antireflection film and the haze decrease. In a case where
the peeling force is 4.0 N/25 mm or less, in the step (8), in a
case where the pressure sensitive film is peeled off, a portion of
the particles (a2) hardly remains on the layer (b), and thus the
reflectivity and the haze of the finally obtained antireflection
film decrease.
In the laminate obtained by the completion of the step (5), a value
(.DELTA.haze) obtained by subtracting the haze of the portion
obtained by removing the portion including the particles (a2) and
the layer (ca) from the laminate from the total haze of the
laminate is preferably 1.00% or less.
The haze can be measured with a film sample of 40 mm.times.80 mm at
25.degree. C. at a relative humidity of 60.degree. % with a haze
meter NDH4000 manufactured by Nippon Denshoku Industries Co., Ltd.
according to JIS-K7136 (2000).
.DELTA.haze may have a negative value. .DELTA.haze is preferably
1.00% or less, more preferably 0.80% or less, and even more
preferably 0.40% or less. In a case where .DELTA.haze is 1.00% or
less, the haze of the antireflection film obtained by using the
laminate obtained by the completion of the step (5) decreases, and
thus it becomes possible to obtain satisfactory antireflection
properties. In a case where .DELTA.haze is 0.40)% or less, in a
case where a black polyethylene terephthalate sheet with a pressure
sensitive adhesive (manufactured by Tomoegawa Co., Ltd.; "clearly
seen") is bonded to an opposite side to the transfer surface of the
antireflection film obtained by using the laminate obtained by the
completion of the step (5), it is possible to obtain an excellent
antireflection film having no antireflection film caused by the
haze.
[Step (6)]
The step (6) is a step of bonding the layer (ca) and the substrate
in the laminate obtained by the method of manufacturing the
laminate according to the embodiment of the present invention.
The method of bonding the layer (ca) and the substrate is not
particularly limited, and well-known methods may be used. Examples
thereof include a roll lamination method.
It is preferable to bond a pressure sensitive film such that the
layer (ca) and the substrate are in contact with each other.
(Substrate)
The substrate is not particularly limited, as long as the substrate
is a substrate having light transmittance that is generally used as
a substrate of an antireflection film, but a plastic substrate or a
glass substrate is preferable.
As the plastic substrate, various kinds thereof can be used.
Examples thereof include a substrate containing a cellulose-based
resin; cellulose acylate (triacetate cellulose, diacetyl cellulose,
and acetate butyrate cellulose) and the like; a polyester resin;
polyethylene terephthalate and the like, a (meth)acrylic resin, a
polyurethane-based resin, polycarbonate, polystyrene, an
olefin-based resin, and the like. A substrate containing cellulose
acylate, polyethylene terephthalate, or a (meth)acrylic resin is
preferable, a substrate containing cellulose acylate is more
preferable, and a cellulose acylate film is particularly
preferable. As the cellulose acylate, substrates and the like
disclosed in JP2012-093723A can be preferably used.
The thickness of the plastic substrate is usually about 10 .mu.m to
1,000 .mu.m. However, in view of satisfactory handleability, high
light transmittance, and sufficient strength, the thickness is
preferably 20 .mu.m to 200 .mu.m and more preferably 20 .mu.m to
100 .mu.m. As the light transmittance of the plastic substrate,
those having light transmittance of the visible light of 90% or
more are preferable.
According to the present invention, before the step (6), a
functional layer may be provided on the substrate. In a case where
a functional layer is provided on the substrate, for convenience, a
laminate of the functional layer and the substrate is called a
"substrate". In a case where a functional layer is provided on the
substrate, the functional layer and the layer (ca) are bonded to
each other in the step (6) and subsequent steps are performed. As
the functional layer, a hard coat layer is preferable.
[Step (7)]
The step (7) is a step of curing the layer (ca) in a state in which
the particles (a2) are buried in the layer obtained by combining
the layer (b) and the layer (ca), and specifically, a step of
curing a portion or all of the compound selected from the group
consisting of the curable compound (a1) and the compound (a1c) in
the layer (ca). Curing all of the compound selected from the group
consisting of the curable compound (a1) and the compound (a1c) in
the layer (ca) includes a case where an uncured compound remains in
a case where curing is performed in a general method. The curing
rate in the step (7) is not particularly limited, but in view of
the film hardness, the curing rate is preferably 60% or more and
more preferably 80% or more.
In the step (7), the substrate bonded in the step (6) and the layer
(ca) can adhere to each other.
The curing in the step (7) is preferably performed in the same
conditions as the conditions described in the step (4-2).
[Step (8)]
The step (8) is a step of peeling a pressure sensitive film from
the laminate obtained from the step (7).
In order to peel the pressure sensitive film in the step (8), as an
index of the adhesion force between the portion including the
particles (a2) and the layer (ca) and the layer (b) in the laminate
obtained by the completion of the step (5), the peeling force
measured in the above measuring method is preferably 0.2 N/25 mm to
4.0 N/25 mm.
It is possible to obtain an antireflection film having a moth eye
structure including an unevenness shape formed by the particles
(a2) on the surface of the layer (ca) after the completion of the
step (8), but the steps (9) and (10) may be performed
afterwards.
[Step (9)]
The step (9) is a step of curing the layer (ca) in a state in which
the particles (a2) protrude from the interface of the layer (ca) on
the opposite side to the interface on the substrate side, and
specifically, a step of curing all of the curable compound (a1) and
the compound (a1c) in the layer (ca). In a case where all of the
curable compound (a1) and the compound (a1c) in the layer (ca) are
cured in the step (7) described above, the step (9) may not be
performed.
It is preferable that the curing in the step (9) is performed in
the same conditions as the conditions as described in the step
(4-2).
In the step (9), it is preferable that irradiation was performed
with ultraviolet rays from the opposite side of the layer (ca) to
the substrate side, to cure the curable compound (a1) and the
compound (a1c) in the layer (ca), in view of manufacturing
suitability.
The layer (ca) after the completion of the step (9) is a layer
including the compound (a1c) in the layer. Here, as described
above, in a case where curing is performed by the general method,
an uncured compound may remain.
[Step (10)]
The step (10) is a step of washing the laminate after the
completion of the step (9) with a solvent.
In the manufacturing of the antireflection film using the laminate
according to the embodiment of the present invention, the pressure
sensitive adhesive hardly remains on the layer (ca) side even in a
case where the support and the layer (b) are peeled off, but in the
step (10), washing may be performed with a solvent (such as methyl
isobutyl ketone, methyl ethyl ketone, and acetone) that dissolves
the pressure sensitive adhesive, without dissolving the substrate
and the layer (ca).
[Laminate]
As described above, the laminate according to the embodiment of the
present invention is a laminate having a support, the layer (b)
including a pressure sensitive adhesive, the particles (a2) having
an average primary particle diameter of 100 nm to 380 nm, and the
layer (ca) including a resin, in which the layer (b) is provided
closer to the support than the layer (ca), the particles (a2) are
buried in the layer obtained by combining the layer (b) and the
layer (ca) and protrude from the interface of the layer (ca) on the
support side, and the portion including the particles (a2) and the
layer (ca) can be peeled off from the layer (b).
The layer (ca) including a resin corresponds to the layer (ca)
after the step (5) in the method of manufacturing the laminate
according to the embodiment of the present invention, and the resin
corresponds to the compound (a1c) obtained by curing the curable
compound (a1) included in the layer (ca) of the step (5).
With respect to the laminate according to the embodiment of the
present invention, it is preferable that a value obtained by
subtracting the haze of the portion obtained by removing the
portion including the particles (a2) and the layer (ca) from the
laminate from the total haze of the laminate is 1.00% or less, in
view of manufacturing an antireflection film having a low haze and
excellent antireflection properties.
In view of transportability and rollability, the laminate according
to the embodiment of the present invention may further have a
peelable member (separator) on a surface of the layer (ca) on the
opposite side to the layer (b) for protecting the surface of the
layer (ca).
The above separator is not particularly limited, as long as the
separator has a material of capable of being peeled off from the
laminate according to the embodiment of the present invention, but
a member which is the same as the temporary support can be used, or
the temporary support itself may be used as the separator.
In the laminate according to the embodiment of the present
invention, it is preferable that the height of the interface of the
layer (ca) on the support side is a half or less of the average
primary particle diameter of the particles (a2) with an interface
on the opposite side as a starting point.
In the laminate according to the embodiment of the present
invention, the film thickness of the layer (ca) is preferably 5% to
70% and more preferably 20% to 40% of the average primary particle
diameter of the particles (a2).
With respect to the surface on the layer (ca) side in the laminate
according to the embodiment of the present invention, the surface
roughness thereof is preferably 30 nm or less and more preferably
10 nm or less.
It is preferable that the laminate according to the embodiment of
the present invention is a laminate in which the portion including
the particles (a2) and the layer (ca) can be peeled off from the
layer (b), and the peeling force measured by the above measurement
method is 0.2 N/25 mm to 4.0 N/25 mm.
In addition, descriptions, specific examples, and preferable ranges
of respective layers and respective components in the laminate of
the present invention are the same as those described in the method
of manufacturing the laminate of the present invention.
[Antireflection Film]
An example of a preferable embodiment of an antireflection film
obtained by the manufacturing method of the present invention is
illustrated in FIG. 3.
The antireflection film 10 in FIG. 3 has the substrate 9 and the
antireflection layer 2. The antireflection layer 2 includes the
particles (a2) (reference numeral 3) and the binder resin film
(reference numeral 4) which is the layer (ca). The particles 3
protrude from the binder resin film 4 to form a moth eye
structure.
(Moth Eye Structure)
The moth eye structure refers to a surface obtained by processing
of a substance (material) for suppressing reflection of light and a
structure of having a periodic microstructure pattern.
Particularly, in a case of having the purpose of suppressing
reflection of visible light, the moth eye structure refers to a
structure having a microstructure pattern with a period of less
than 780 nm. It is preferable that the period of the microstructure
pattern is less than 380 nm, the color of reflected light becomes
small. It is preferable that the period of the uneven shape of the
moth eye structure is 100 nm or more, light having a wavelength of
380 nm can recognize a microstructure pattern and is excellent in
antireflection properties. Whether the moth eye structure is
present can be checked by observing the surface shape with a
scanning electron microscope (SEM)), an atomic force microscope
(AFM) or the like, and checking whether the microstructure pattern
can be formed.
In the uneven shape the antireflection layer of the antireflection
film manufactured by the manufacturing method of the present
invention, it is preferable that B/A which is the ratio of a
distance A between the peaks of the adjacent protrusions and a
distance B between the center between the peaks of the adjacent
protrusions and the recessed part is 0.4 or more. In a case where
B/A is 0.4 or more, the refractive index gradient layer in which
the depth of the recessed part is greater than the distance between
the protrusions and the refractive index gradually changes from the
air to the inside of the antireflection layer can be formed, and
thus the reflectivity can be further reduced.
B/A is more preferably 0.5 or more. In a case where B/A is 0.5 or
more, the distance A between the peaks of the adjacent protrusions
(protrusions formed by the particles) becomes the particle diameter
or more, such that the recessed part is formed between particles.
As a result, it is assumed that, in a case where both of the
interface reflection due to a region having a sharp change on the
refractive index depending on the curvature of the upper side of
the protrusion and the interface reflection due to a region having
a sharp change on the refractive index depending on the curvature
of the recessed part between the particles are present, in addition
to the refractive index gradient layer effect by the moth eye
structure, the reflectivity is more effectively reduced.
B/A can be controlled by the volume ratio of the binder resin and
the particles in the antireflection layer after curing. Therefore,
it is important to appropriately design the formulation ratio of
the binder resin and the particles. In a case where the binder
resin permeates the layer (b) including the pressure sensitive
adhesive in the step of preparing the moth eye structure or
volatilizes, the volume ratio of the binder resin and the particles
in the antireflection layer becomes different from the formulation
ratio in the composition for forming the antireflection layer, and
thus it is important to appropriately set the matching with the
layer (b) including the pressure sensitive adhesive in the laminate
according to the embodiment of the present invention.
In order to realize the low reflectivity and suppress the
occurrence of haze, it is preferable that the particles for forming
the protrusions are uniformly spread at an appropriate filling
rate. In view of the above, the content of the particles (a2) for
forming the protrusions is preferably adjusted such that the
inorganic particles are uniform over the entire antireflection
layer. The filling rate can be measured as the area occupation
ratio (particle occupancy ratio) of the inorganic particles located
most surface side in a case of observing the particles (a2) forming
the protrusions from the surface by scanning electron microscope
(SEM) or the like, and is 25% to 64%, preferably 25% to 50%, and
more preferably 30% to 45%.
The uniformity of the surface of the antireflection film can be
evaluated by haze. With respect to the measurement, a film sample
of 40 mm.times.80 mm can be measured according to JIS-K 7136 (2000)
with a haze meter NDH 4000 manufactured by Nippon Denshoku
Industries Co., Ltd. at 25.degree. C. and a relative humidity of
606. In a case where particles aggregated and were not uniform, the
haze was high. It is preferable that the haze was lower. The value
of the haze is preferably 0.0% to 3.0%, more preferably 0.0% to
2.5%, and even more preferably 0.0% to 2.0%.
[Hard Coat Layer]
According to the present invention, a hard coat layer can further
be provided between the substrate and the layer (ca). In the case
where the hard coat layer is provided on the substrate, as
described above, according to the present invention, the hard coat
layer on the substrate is collectively referred to as the substrate
in some cases.
The hard coat layer is preferably formed by a crosslinking reaction
or a polymerization reaction of a curable compound (preferably an
ionizing radiation curable compound) which is a compound having a
polymerizable group. For example, the hard coat layer can be formed
by coating the substrate with a coating composition including an
ionizing radiation curable polyfunctional monomer or a
polyfunctional oligomer and subjecting the polyfunctional monomer
or the polyfunctional oligomer to crosslinking reaction or
polymerization reaction.
As the functional group (polymerizable group) of the ionizing
radiation curable polyfunctional monomer or polyfunctional
oligomer, those having light, electron beams, or radiation
polymerizability are preferable. Among them, a photopolymerizable
functional group is preferable.
Examples of the photopolymerizable functional group include
unsaturated polymerizable functional groups such as a
(meth)acryloyl group, a vinyl group, a styryl group, and an allyl
group. Among them, a (meth)acryloyl group is preferable.
Specifically, a compound which is the same as the curable compound
(a1) described above can be used.
In view of applying sufficient durability and impact resistance in
a film the thickness of the hard coat layer is usually about 0.6
.mu.m to 50 .mu.m and preferably 4 .mu.m to 20 .mu.m.
The strength of the hard coat layer is preferably H or more and
more preferably 2H or more in a pencil hardness test. Further, in
the Taber test according to JIS K5400, it is more preferable in a
case where an abrasion amount of a test piece before and after the
test is smaller.
The hard coat layer according to the present invention may include
cellulose acylate in a region within 1 pin in the film thickness
direction from the interface with the antireflection layer.
As the cellulose acylate, substrates and the like disclosed in
<0072> to <0084> of JP2012-093723A can be preferably
used.
The hard coat layer including cellulose acylate in a region within
1 .mu.m from the interface with the antireflection layer in the
film thickness direction can be formed, for example, by coating a
substrate (a cellulose acylate film or the like) including
cellulose acylate with a composition for forming a hard coat layer
having permeability to the substrate and containing a solvent and a
curable compound, causing the curable compound permeate the
substrate, and curing the composition. The hard coat layer can also
be formed by mixing and curing cellulose acylate and the curable
compound.
In a case where the antireflection film is cut with a microtome and
the cross section was analyzed with a time-of-flight secondary ion
mass spectrometer (TOF-SIMS), the hard coat layer can be measured
as a portion a cured product of cellulose acylate and the ionizing
radiation curable compound is detected, and the film thickness of
this region can also be measured from the cross-sectional
information of the TOF-SIMS in the same manner.
The hard coat layer can be measured, for example, by detecting
another layer between the substrate and the antireflection layer by
observing the cross section by a reflection spectroscopic film
thickness meter or a transmission electron microscope (TEM) by
using light interference. As the reflective spectroscopic film
thickness meter, FE-3000 (manufactured by Otsuka Electronics Co.,
Ltd.) or the like can be used.
According to the present invention, for example, in a case where
the coating film is ultraviolet curable, the hard coat layer can be
half-cured by appropriately adjusting the oxygen concentration in a
case of curing and the ultraviolet irradiation amount. It is
preferable that the coating film is cured by being irradiated with
ultraviolet rays in an irradiation amount of 1 mJ/cm.sup.2 to 300
mJ/cm.sup.2 by an ultraviolet lamp. The irradiation amount is more
preferably 5 mJ/cm.sup.2 to 100 mJ/cm.sup.2 and still more
preferably 10 mJ/cm.sup.2 to 70 mJ/cm.sup.2. At the time of
irradiation, the energy may be applied at once or can be applied in
a divided manner. As the ultraviolet lamp type, a metal halide
lamp, a high pressure mercury lamp, or the like is suitably
used.
The oxygen concentration at the curing is preferably 0.05 to 5.0
vol %, more preferably 0.1 to 2 vol %, and particularly preferably
0.1 to 1 vol %.
(Solvent Having Permeability to Cellulose Acylate)
The composition for forming the hard coat layer preferably contains
a solvent (also referred to as "permeable solvent") having
permeability to cellulose acylate.
The solvent having permeability with respect to cellulose acylate
is a solvent having solubility to a substrate (cellulose acylate
substrate) containing cellulose acylate.
Here, the solvent having solubility to a cellulose acylate
substrate means a solvent in which, after the cellulose acylate
substrate having a size of 24 mm.times.36 mm (thickness: 80 .mu.m)
is immersed in a 15 ml bottle including the above solvent at room
temperature (25.degree. C.) for 60 seconds and then taken out, in a
case where the immersed solution is subjected to gel permeation
chromatography (GPC), the peak surface area of cellulose acylate is
400 mV/sec or more. Otherwise, the solvent means a solvent of which
the shape thereof is lost by causing a cellulose acylate substrate
having a size of 24 mm.times.36 mm (thickness 80 .mu.m) to stand in
a 15 ml bottle including the above solvent at room temperature
(25.degree. C.) for 24 hours and appropriately shaking the bottle
or the like such that the cellulose acylate substrate is completely
dissolved and which has solubility to the cellulose acylate
substrate.
As the permeable solvent, methyl ethyl ketone (MEK), dimethyl
carbonate, methyl acetate, acetone, methylene chloride, and the
like can be preferably used, but the present invention is not
limited thereto. Methyl ethyl ketone (MEK), dimethyl carbonate, and
methyl acetate are more preferable.
The composition for forming a hard coat layer may include a solvent
in addition to the permeable solvent (for example, ethanol,
methanol, 1-butanol, isopropanol (IPA), methyl isobutyl ketone
(MIBK), and toluene).
In the composition for forming a hard coat layer, the content of
the permeable solvent is preferably 50 mass % to 100 mass % and
more preferably 70 mass % to 100 mass % with respect to the total
mass of the solvent included in the composition for forming a hard
coat layer.
The solid content concentration of the composition for forming a
hard coat layer is preferably 20 mass % to 70 mass % and more
preferably 30 mass % to 60 mass %.
(Other Components)
In addition to the above components, a solvent, a polymerization
initiator, an antistatic agent, an antiglare agent and the like can
be appropriately added to the composition for forming a hard coat
layer. Various additives such as reactive or non-reactive leveling
agents and various sensitizing agents may be mixed.
(Polymerization Initiator)
If necessary, radicals and cationic polymerization initiators and
the like may be suitably selected to be used. These polymerization
initiators are decomposed by light irradiation and/or heating to
generate radicals or cations and promote radical polymerization and
cationic polymerization.
(Antistatic Agent)
As specific examples of the antistatic agent, antistatic agents
well known in the related art such as quatemary ammonium salt, a
conductive polymer, and a conductive fine particles can be used,
though the antistatic agents are particularly limited. However, in
view of the low cost and the ease of handling, an antistatic agent
having quaternary ammonium salt is preferable.
(Refractive Index Adjusting Agent)
For the purpose of controlling the refractive index of the hard
coat layer, a high refractive index monomer or inorganic particles
can be added as a refractive index adjusting agent. In addition to
the effect of controlling the refractive index, the inorganic
particles also have an effect of suppressing curing shrinkage due
to the crosslinking reaction. According to the present invention,
after the hard coat layer is formed, a polymer generated by
polymerizing the polyfunctional monomer and/or the high refractive
index monomer or the like and inorganic particles dispersed therein
are collectively referred to as a binder.
(Leveling Agent)
As specific examples of the leveling agent, leveling agents
well-known in the related art such as fluorine-based or
silicone-based leveling agents can be used. The composition for
forming a hard coat layer to which the leveling agent is added can
provide coating stability to the surface of the coating film in a
case of coating or drying.
The antireflection film manufactured by the manufacturing method of
the present invention can be appropriately used as a polarizing
plate protective film.
The polarizing plate protective film using the antireflection film
manufactured by the manufacturing method of the present invention
can be bonded to a polarizer to form a polarizing plate and can be
appropriately used in a liquid crystal display device or the
like.
[Polarizing Plate]
The polarizing plate is a polarizing plate having a polarizer and
at least one of the protective films for protecting the polarizer,
and it is preferable that at least one of the protective films is
an antireflection film manufactured by the method for manufacturing
the antireflection film of the present invention.
The polarizer includes an iodine-based polarizer, a dye-based
polarizer using a dichroic dye, and a polyene-based polarizer. The
iodine-based polarizer and the dye-based polarizer can be generally
manufactured by using a polyvinyl alcohol-based film.
[Cover Glass]
The antireflection film manufactured by the method for
manufacturing an antireflection film of the present invention can
also be applied to a cover glass.
[Image Display Device]
The antireflection film manufactured by the method for
manufacturing an antireflection film of the present invention can
also be applied to an image display device.
Examples of the image display device include a display device using
a cathode ray tube (CRT), a plasma display panel (PDP), an
electroluminescent display (ELD), a vacuum fluorescent display
(VFD), a field emission display (FED), and a liquid crystal display
device (LCD), and a liquid crystal display device is particularly
preferable.
Generally, a liquid crystal display device has a liquid crystal
cell and two polarizing plates disposed on both sides of the liquid
crystal cell, and the liquid crystal cell carries a liquid crystal
between the two electrode substrates. One optically anisotropic
layer may be disposed between the liquid crystal cell and one
polarizing plate, or two optically anisotropic layers may be
disposed between the liquid crystal cell and both polarizing
plates. As the liquid crystal cell, liquid crystal cells of various
driving methods such as a Twisted Nematic (TN) mode, a Vertically
Aligned (VA) mode, an Optically Compensatory Bend (OCB) mode, and
an In-Plane Switching (IPS) mode can be applied.
EXAMPLES
Hereinafter, the present invention is specifically described with
reference to the examples. A material, a reagent, a substance
quantity, a ratio thereof, an operation, and the like provided in
the following examples can be suitably changed without departing
from the gist of the present invention. Accordingly, the scope of
the present invention is not limited to the following specific
examples.
Example 1
(Preparation of Composition for Forming Hard Coat Layer)
Each component was added in the following composition, and the
obtained composition was introduced to a mixing tank, stirred, and
filtrated with a polypropylene filter having a pore size of 0.4
.mu.m so as to obtain a hard coat layer coating solution.
(Hard Coat Layer Coating Solution HC-1)
TABLE-US-00001 A-TMMT . . . 33.6 parts by mass IRGACURE 127 . . .
1.4 parts by mass Methyl ethyl ketone (MEK) . . . 35.8 parts by
mass Methyl acetate . . . 29.2 parts by mass
(Hard Coat Layer Coating Solution HC-2)
TABLE-US-00002 A-TMMT . . . 24.1 parts by mass AD-TMP . . . 11.8
parts by mass DPCA-60 . . . 12.0 parts by mass IRGACURE 127 . . .
2.1 parts by mass AS-1 . . . 6.9 parts by mass Ethanol . . . 0.4
parts by mass Ethanol . . . 6.7 parts by mass 1-Butanol . . . 4.8
parts by mass Methyl ethyl ketone (MEK) . . . 16.8 parts by mass
Methyl acetate . . . 14.4 parts by mass FP-1 . . . 0.05 parts by
mass
A-TMMT: Pentaervthritol tetraacrylate (manufactured by Shin
Nakamura Chemical Co., Ltd.)
IRGACURE 127: Photopolymerization initiator (manufactured by BASF
Japan Ltd.)
AD-TMP: Ditrimethylolpropane tetraacrylate (manufactured by
Shin-Nakamura Chemical Co., Ltd., NK ESTER)
DPCA-60: Polyfunctional acrylate oligomer containing caprolactone
structure (manufactured by Nippon Kayaku Co., Ltd., KAYARAD)
AS-1: A compound AS-1 corresponding the above patent document (A-6)
was prepared in the same manner except that the reaction
temperature and time of Synthesis Example 6 of JP4678451B were set
as 70.degree. C. and 6 hours. The completed compound AS-1 was a
quaternary ammonium salt polymer having an ethylene oxide chain,
and the weight-average molecular weight measured by GPC was about
60,000.
FP-1: Fluorine-containing compound represented by the following
formula
##STR00002##
[Synthesis of Silica Particles P1]
67.54 kg of methyl alcohol and 26.33 kg of 28 mass % aqueous
ammonia (water and catalyst) were introduced to a reactor with
capacity of 200 L comprising a stirrer, a dropwise adding device,
and a thermometer, and the liquid temperature was adjusted to
33.degree. C. while stirring. On the other hand, a solution
prepared by dissolving 12.70 kg of tetramethoxysilane in 5.59 kg of
methyl alcohol was introduced to the dropwise adding device. While
the liquid temperature in the reactor was maintained to 33.degree.
C., the above solution was added dropwise from the dropwise adding
device over 44 minutes. After the dropwise addition was completed,
stirring was continued while the liquid temperature was maintained
to the above temperature for 44 minutes, and hydrolysis and
condensation of tetramethoxy silane were performed, so as to obtain
a dispersion liquid containing a silica particle precursor. This
dispersion liquid was air-dried under the conditions of a heating
tube temperature of 175.degree. C. and a reduced pressure degree of
200 torr (27 kPa) by using an instantaneous vacuum evaporator (CRUX
SYSTEM CVX-8B model manufactured by Hosokawa Micron Corporation),
so as to obtain silica particles P1.
The average primary particle diameter of the silica particles P1
was 170 nm, the dispersion degree (CV value) of the particle
diameter was 3.3%, and the indentation hardness was 340 MPa.
[Manufacturing of Calcined Silica Particles P2]
5 kg of the silica particles P1 were introduced to a crucible,
calcined at 900.degree. C. for two hours in an electric furnace,
cooled, and then pulverized by using a pulverizer to obtain the
calcined silica particles before classification. Disintegration and
classification were performed by using a jet pulverizing classifier
(IDS-2 model manufactured by Nippon Pneumatic Mfg. Co., Ltd.) to
obtain calcined silica particles P2.
[Manufacturing of silane coupling agent-treated silica particles
P3]5 kg of the calcined silica particles P2 were introduced to a
Henschel mixer (FM20J model manufactured by Nippon Coke &
Engineering Co., Ltd.) having a capacity of 20 L comprising a
heating jacket. A solution obtained by dissolving 45 g of
3-acryloxvpropyltrimethoxysilane (KBM 5103 manufactured by
Shin-Etsu Chemical Co., Ltd.) in 90 g of methyl alcohol was added
dropwise to a portion in which the calcined silica particles P2
were stirred and mixed. Thereafter, the temperature was raised to
150.degree. C. over about one hour while mixing and stirring, and
the mixture was maintained at 150.degree. C. for 12 hours, and the
heat treatment was performed. Thereafter, in the heat treatment,
the attachment on the wall was scraped off while the scraping
device was rotated constantly in the opposite direction to the
stirring blade. If necessary, the deposits on the wall were scraped
off with a spatula. After heating, cooling was performed, and
disintegration and classification were performed by using a jet
pulverizing classifier, so as to obtain a silane coupling agent
treated silica particles P3.
The average primary particle diameter of the silane coupling agent
treated silica particles P3 was 171 nm, the dispersion degree (CV
value) of the particle diameter was 3.3%, and the indentation
hardness was 470 MPa.
[Manufacturing of Silica Particle Dispersion Liquid PA-1]
50 g of the silica particles P3 treated with a silane coupling
agent, 200 g of MEK, and 600 g of zirconia beads having a diameter
of 0.05 mm were introduced in a 1 L bottle having a diameter of 12
cm, set in a ball mill V-2M (IRIE SHOKAI Co., Ltd.), and dispersed
for 10 hours at 250 rotation/min. In this manner, a silica particle
dispersion liquid PA-1 (concentration of solid content: 20 mass %)
was manufactured.
[Synthesis of Compound C3]
19.3 g of 3-isocyanatepropyltrimethoxy silane, 3.9 g of glycerin
1,3-bisacrylate, 6.8 g of 2-hydroxyethyl acrylate, 0.1 g of
dibutyltin dilaurate, and 70.0 g of toluene were added to a flask
equipped with a reflux condenser and a thermometer and were stirred
at room temperature for 12 hours. After stirring, 500 ppm of
methylhydroquinone was added, and distillation under reduced
pressure was performed, so as to obtain compound C3.
##STR00003##
[Preparation of Composition for Forming Layer (a)]
Each component was introduced to a mixing tank so as to have the
composition, was stirred for 60 minutes, and was dispersed by an
ultrasonic disperser for 30 minutes to obtain a coating
solution.
Composition (A-1)
TABLE-US-00003 U-15HA . . . 1.4 parts by mass Compound C3 . . . 1.5
parts by mass A-TMPT . . . 1.7 parts by mass Triethyl citrate . . .
4.1 parts by mass IRGACURE 127 . . . 0.2 parts by mass Compound P .
. . 0.1 parts by mass FP-2 . . . 0.1 parts by mass Silica particle
dispersion 32.3 parts by mass liquid PA-1 . . . Ethanol . . . 12.7
parts by mass Methyl ethyl ketone . . . 33.2 parts by mass Acetone
. . . 12.7 parts by mass
Composition (A-2)
TABLE-US-00004 U-15HA . . . 1.4 parts by mass Compound C3 . . . 1.5
parts by mass A-TMPT . . . 1.7 parts by mass Dimethyl suberate . .
. 4.1 parts by mass IRGACURE 127 . . . 0.2 parts by mass Compound P
. . . 0.1 parts by mass FP-2 . . . 0.1 parts by mass Silica
particle dispersion 32.3 parts by mass liquid PA-1 . . . Ethanol .
. . 12.7 parts by mass Methyl ethyl ketone . . . 33.2 parts by mass
Acetone . . . 12.7 parts by mass
Composition (A-3)
TABLE-US-00005 U-15HA . . . 1.4 parts by mass Compound C3 . . . 1.5
parts by mass A-TMPT . . . 1.7 parts by mass KBM-4803 . . . 4.1
parts by mass IRGACURE 127 . . . 0.2 parts by mass Compound P . . .
0.1 parts by mass FP-2 . . . 0.1 parts by mass Silica particle
dispersion 32.3 parts by mass liquid PA-1 . . . Ethanol . . . 12.7
parts by mass Methyl ethyl ketone . . . 33.2 parts by mass Acetone
. . . 12.7 parts by mass
U-15HA, a compound C3, and A-TMPT are the curable compound
(a1).
The compounds used are provided below.
U-15HA (manufactured by Shin Nakamura Chemical Co., Ltd.): Urethane
acrylate
A-TMPT: Polyfunctional acrylate (manufactured by Shin-Nakamura
Chemical Co., Ltd.)
Triethyl citrate: Ester-based compound (manufactured by Tokyo
Chemical Industry Co., Ltd.)
Dimethyl suberate: Ester-based compound (manufactured by Tokyo
Chemical Industry Co., Ltd.)
KBM-4803: Silane coupling agent having a reactive group other than
a radical reactive group (manufactured by Shin-Etsu Chemical Co.,
Ltd.)
IRGACURE 127: Photopolymerization initiator (manufactured by BASF
Japan Ltd.)
Compound P: Photoacid generating agent represented by the following
structural formula (manufactured by Fujifilm Wako Pure Chemical
Corporation)
##STR00004##
FP-2: Fluorine-containing compound represented by the following
formula
##STR00005##
<Preparation of Antireflection Film 1>
(Step (1): Coating of Layer (a))
A 100 .mu.m polyethylene terephthalate film (FD 100M, manufactured
by Fujifilm Corporation) as a temporary support was coated with the
composition (A-1) by 2.8 ml/m.sup.2 by using a die coater, and the
composition was dried at 30.degree. C. for 90 seconds.
(Step (2): Pre-Exposure of Layer (a))
While nitrogen purging was performed so as to be an atmosphere in
which an oxygen concentration of 1.4 vol %, light irradiation was
performed from the layer (a) side at an irradiation amount of 2.4
mJ/cm.sup.2 and the illuminance of 0.60 mW by using a high-pressure
mercury lamp (manufactured by Dr. Honle AG, model number: 33351N
and Part no.: LAMP-HOZ 200 D24 U 450 E), so as to cure a part of
the curable compound (a1) and to obtain the layer (ca). With
respect to the measurement of the irradiation amount, HEAD SENSER
PD-365 was mounted on an eye ultraviolet ray integrating
accumulation light meter UV METER UVPF-A1 manufactured by Eye
Graphics, Inc., and the measurement was performed in a measurement
range of 0.00.
(Step (3): Bonding of Pressure Sensitive Film)
Subsequently, the pressure sensitive layer obtained by peeling off
a release film from a protective film (MASTAC TFB AS3-304)
manufactured by Fujimori Kogyo Co., Ltd. was bonded to the layer
(a) such that the pressure sensitive adhesive layer (layer (b)) on
the layer (a) side. The bonding was performed at a speed of 1 by
using a commercial laminator Bio330 (manufactured by DAE-EL
Co.)
The protective film herein refers to a laminate formed of the
support/the pressure sensitive adhesive layer/the release film, and
a laminate obtained by peeling off the release film from the
protective film and formed of the support/the pressure sensitive
adhesive layer was a pressure sensitive film.
The protective film used is as below.
MASTACK TFB AS3-304 (manufactured by Fujimori Kogyo Co., Ltd.,
Optical protective film with antistatic function) (hereinafter also
referred to as "AS3-304")
Support: Polyester film (thickness: 38 .mu.m)
Thickness of pressure sensitive adhesive layer: 20 .mu.m
Maximum transmittance at wavelength of 250 nm to 300 nm in state in
which release film was peeled: Less than 0.1%
The transmittance was measured using an ultraviolet-visible-near
infrared spectrophotometer UV3150 manufactured by Shimadzu
Corporation.
(Step (4): Permeation of Curable Compound (a1) into Layer (b))
After the pressure sensitive film was bonded, the layer (b) was
left under the environment of 25.degree. C. for five minutes such
that a portion of the curable compound (a1) permeates the layer
(b).
(Step (4-2): Partial Curing of Layer (Ca))
Subsequently, irradiation was performed with ultraviolet rays
having an illuminance of 150 mW/cm.sup.2 and an irradiation amount
of 600 mJ/cm.sup.2 from the opposite side of the support to the
layer (ca) by using an air cooling metal halide lamp (manufactured
by Eye Graphics Co., Ltd.) of 160 W/cm while purging was performed
with nitrogen such that the atmosphere had an oxygen concentration
of 0.01 vol % or less, so as to cure a portion of the layer
(ca).
(Step (5): Manufacturing Peeling Laminate of Temporary Support)
FD100M which was the temporary support was peeled off from the
laminate in the 180.degree. direction at the speed of 30 m/min. The
laminate 1 which is an example of the present invention was
manufactured in this manner.
(Manufacturing Substrate with Hard Coat Layer)
--Forming of hard coat layer-- The substrate (TJ25, manufactured by
Fujifilm Corporation) was coated with the hard coat layer coating
solution HC-1 by using a die coater at 17.3 ml/m.sup.2. After
drying was performed at 90.degree. C. for one minute, while
nitrogen purging is performed so as to have an atmosphere of an
oxygen concentration of approximately 1.5 vol %, irradiation is
performed with ultraviolet rays in an illuminance of 18 mW/cm.sup.2
and in an irradiation amount of 10 mJ/cm.sup.2 by using an air
cooling metal halide lamp (manufactured by Eye Graphics Co., Ltd.)
of 160 W/cm so as to cure a coating layer, such that a hard coat
layer having a thickness of 8 .mu.m is formed. The substrate with a
hard coat layer is set as HC-1.
(Step (6): Bonding of Substrate)
The hard coat layer side of the substrate HC-1 with a hard coat
layer was bonded to the layer (ca) side of the laminate 1 from
which the temporary support was removed in the step (5). The
bonding was performed at a speed of 1 by using a commercial
laminator Bio330 (manufactured by DAE-EL Co.)
(Step (7): Partial Curing of Layer (Ca))
Subsequently, irradiation was performed with ultraviolet rays
having an illuminance of 150 mW/cm.sup.2 and an irradiation amount
of 600 mJ/cm.sup.2 from the opposite side of the support to the
layer (ca) by using an air cooling metal halide lamp (manufactured
by Eye Graphics Co., Ltd.) of 160 W/cm while purging was performed
with nitrogen such that the atmosphere had an oxygen concentration
of 0.01 vol % or less, so as to cure a portion of the layer
(ca).
(Step (8): Peeling of Pressure Sensitive Film)
A pressure sensitive film (film obtained by peeling off the release
film from MASTACK TFB AS3-304) was peeled off from the prepared
laminate.
(Step (9): Curing of Layer (Ca))
Subsequently, irradiation was performed with ultraviolet rays
having an illuminance of 150 mW/cm.sup.2 and an irradiation amount
of 600 mJ/cm.sup.2 from the opposite side the layer (ca) to the
substrate of by using an air cooling metal halide lamp
(manufactured by Eye Graphics Co., Ltd.) of 160 W/cm while purging
was performed with nitrogen such that the atmosphere had an oxygen
concentration of 0.01 vol % or less, so as to cure the layer
(ca).
[Step (10): Washing]
Subsequently, methyl isobutyl ketone was applied to flow over the
surface on which the pressure sensitive film was bonded so as to
wash away a residue of the adhesive layer. Thereafter, the film was
dried at 25.degree. C. for 10 minutes to obtain an antireflection
film 1.
Laminates 2 to 9 and antireflection films 2 to 9 were manufactured
in the same manner as in the manufacturing of the laminate 1 and
the antireflection film 1, except that the kind of the temporary
support, the kind of the composition for forming the layer (a), the
kind of the pressure sensitive film (protective film), the exposure
amount of the pre-exposure in the step (2), the kind of the hard
coat layer coating solution used, or the kind of the substrate were
changed. In addition, as described above, the pressure sensitive
film was a laminate which was obtained by peeling off the release
film from the protective film and which consists of the support and
the pressure sensitive adhesive layer. The types of protective film
used are presented in Table 1.
Except for the above, the temporary support used was as below:
ZF14: 100 .mu.m cycloolefin-based resin film (ZEONOR ZF-14,
(manufactured by) Zeon Corporation)
Except for the above, the protective film used was as below:
MASTACK TFB AS3-310 (manufactured by Fujimori Kogyo Co., Ltd.,
Optical protective film with antistatic function) (hereinafter also
referred to as "AS3-310")
Support: Polyester film (thickness: 38 .mu.m)
Thickness of pressure sensitive adhesive layer: 15 .mu.m
Maximum transmittance at wavelength of 250 nm to 300 nm in state in
which release film was peeled: Less than 0.1%
Except for the above, the substrate used was as below.
HC-2: A substrate with a hard coat layer manufactured in the same
manner in the manufacturing of the substrate HC-1 with a hard coat
layer, except that a hard coat layer coating solution HC-2 was used
instead of the hard coat layer coating solution HC-1.
FD100M: A 100 .mu.m polyethylene terephthalate film (FD 100M,
(manufactured by) Fujifilm Corporation)
(Method of Evaluating Antireflection Film)
Various properties of the antireflection film were evaluated by the
following method. Results thereof are as presented in Table 1.
(Integrated Reflectivity)
In a state in which after the back side (substrate side) of the
antireflection film was roughened with sandpaper, an oily black ink
(magic ink for supplement: Teranishi Chemical Industry Co., Ltd.)
was applied such that backside reflection was eliminated, an
adapter ARV-474 was attached to a spectrophotometer V-550
(manufactured by JASCO Corporation), in the wavelength range of 380
to 780 nm, the integrated reflectivity at an incidence angle of
5.degree. was measured, and the average reflectivity was
calculated, so as to evaluate the antireflection performance.
(Total Haze)
The uniformity of the surface was evaluated by a haze value. The
total haze value (%) of the obtained antireflection film was
measured in accordance with JIS-K7136 (2000). A haze meter NDH4000
manufactured by Nippon Denshoku Industries Co., Ltd. was used in
the device. In a case where particles aggregated and were not
uniform, the haze increased, and thus a low haze is preferable.
(Transferability)
A black polyethylene terephthalate sheet with a pressure sensitive
adhesive (manufactured by Tomoegawa Co., Ltd.: "clearly seen") was
laminated on the opposite side to the transfer surface (surface
having antireflection layer) of the antireflection film cut by the
size of 30 cm.times.30 cm and was visually observed, so as to
evaluate transferability according to the evaluation standard. A
black polyethylene terephthalate sheet with a pressure sensitive
adhesive was bonded to the antireflection film and was visually
observed, a region (transferred region) in which reflectivity
decreased more than in the substrate before the antireflection
layer was transferred, and a region (non-transferred region) in
which reflectivity increased to be equivalent to the original
substrate were able to be visually checked. In a case where the
transfer unevenness was generated, in the transferred region, the
unevenness of the reflectivity was visually observed. The
proportion of the transferred region was quantified by filling the
non-transferred area with a white felt tip pen, capturing an image
with a scanner, and obtaining the area.
(Evaluation Standard)
A: The ratio of the region capable of being transferred was 90% or
more, and the transfer unevenness was not visually recognized.
B: The ratio of the region capable of being transferred was 90% or
more, and the transfer unevenness was visually recognized.
C: The ratio of the region capable of being transferred was 80% or
more and less than 90%.
D: The ratio of the region capable of being transferred was less
than 80%.
The transferability is required to be A to C, in practice, and A
and B are more preferable, and A is most preferable, since the
reliability of the antireflection film produced by transfer is
high.
[Method of Evaluating Laminate]
The various properties of the laminates 1 to 9 manufactured by the
completion of the step (5) were evaluated. Results thereof are as
presented in Table 1.
(.DELTA.Haze)
The hazes of the laminate obtained by the completion of the step
(5) and the pressure sensitive film used were measured on the
support side by incidence and were subtracted to obtain
.DELTA.haze. With respect to the measurement of the haze, each
sample of 40 mm.times.80 mm can be measured according to JIS-K 7136
(2000) with a haze meter NDH 4000 manufactured by Nippon Denshoku
Industries Co., Ltd. at 25.degree. C. and a relative humidity of
60%.
(Surface Roughness)
In the laminate obtained the completion of the step (5), the
surface roughness of the surface on the layer (ca) side was
measured. As the surface roughness, a value calculated from the
surface unevenness shape obtained by the measurement with SPA-400
(manufactured by Hitachi High-Tech Science Corporation) under
measurement conditions of a measurement range 5 .mu.m.times.5
.mu.m, a measurement mode of DFM, and a measurement frequency of 2
Hz was used.
(Peeling Force)
A peeling force was measured in a case where the particles (a2) and
the layer (ca) on the surface on an opposite side to the support of
the transfer member (a laminate obtained by the completion of the
step (5)) having a width of 25 mm were fixed to to the glass
substrate having a thickness of 1.1 mm by using an adhesive, and
the portion including the particles (a2) and the layer (ca) and the
layer (b) were peeled off in the 90.degree. direction and at the
speed of 1,000 mm/min. Here, a case where peeling was not performed
on the interface between the portion including the particles (a2)
and the layer (ca) and the layer (b) was referred to as "not
measurable. The determination on whether the interfacial peeling
was performed or not was performed by observing the layer (b) after
the peeling with SEM or AFM, and checking whether the particles
were observed or not.
TABLE-US-00006 TABLE 1 Step (1) Step (2) Step (4-2) Composition
Ultraviolet Step (3) Ultraviolet for irradiation Kind of
irradiation Antireflection Temporary forming amount protective
amount Kind of Laminate film substrate layer (a) [mJ/cm.sup.2] film
[mJ/cm.sup.2] substrate Example 1 1 1 FD100M A-1 2.4 AS3-304 600
HC-1 Example 2 2 2 FD100M A-2 3.9 AS3-304 600 HC-1 Example 3 3 3
FD100M A-3 5.2 AS3-304 600 HC-1 Example 4 4 4 ZF14 A-1 2.4 AS3-304
600 HC-1 Example 5 5 5 FD100M A-1 2.4 AS3-304 600 FD100M Example 6
6 6 FD100M A-1 2.4 AS3-304 600 HC-2 Example 7 7 7 FD100M A-1 2.4
AS3-310 600 HC-1 Example 8 8 8 FD100M A-1 1.0 AS3-304 600 HC-1
Comparative 9 9 FD100M A-1 0 AS3-304 600 HC-1 Example 1 Step (7)
Step (9) Evaluation of Properties of Ultraviolet Ultraviolet
transfer member antireflection film irradiation irradiation Surface
Total amount amount .DELTA.haze Peeling force roughness of
Integrated haze [mJ/cm.sup.2] [mJ/cm.sup.2] [%] [N/25 mm] layer
(ca) reflectivity [%] Transferability Example 1 600 600 0.0 8 1.5
0.6% 1.3 A Example 2 600 600 0.2 12 1.2 0.9% 1.5 B Example 3 600
600 -0.1 8 1.4 0.6% 1.1 A Example 4 600 600 0.5 16 1.5 1.0% 2.0 B
Example 5 600 600 0.0 8 1.5 0.8% 1.5 C Example 6 600 600 0.0 8 1.5
0.6% 1.3 A Example 7 600 600 0.0 10 2.0 0.7% 1.4 A Example 8 600
600 0.9 25 0.5 1.6% 2.4 C Comparative 600 600 1.7 38 Not 3.0% 3.4 D
Example 1 measurable
It was understood that the laminates 1 to 8 according to Examples 1
to 8 of the present invention had small .DELTA.haze value, the
small surface roughness, and an appropriate peeling force, so as to
have satisfactory transferability. In contrast, with respect to the
laminate of Comparative Example 1, since the exposure was not
performed in the step (2), the particles (a2) were not regularly
arranged, the .DELTA.haze value and the surface roughness were
increased, and thus the transferring to the substrate was not
satisfactory.
It is understood that the antireflection films 1 to 8 obtained by
the manufacturing method of the present invention by using the
laminate of Examples 1 to 8 had low haze and satisfactory
antireflection properties.
The laminate according to the embodiment of the present invention
is a transfer member having satisfactory transferability and can be
applied to a substrate for forming antireflection films having
various forms.
EXPLANATION OF REFERENCES
1: temporary support 2: antireflection layer 3: particle (a2) 4:
layer (a) or layer (ca) 5: support 6: layer (b) 7: pressure
sensitive film 8: laminate 9: substrate 10: antireflection film A:
distance between peaks of adjacent protrusions B: distance between
the center of peaks of adjacent protrusions and recessed part
* * * * *